A Text Book of Practical Science Class X

A Text Book of Practical Science Class X

Authors: Prakash Parajuli Bishnu Parajuli MSc, Physics MSc, Physics

Editor: Mr. Kamal Prasad Sapkota M.Sc. (Chemistry), M.A.

ASIA PUBLICATIONS (PVT.) LTD. Bagbazar, Kathmandu, Nepal Tel: 4232879, 4239174, 4257462 Fax.: 4239190 i

ii

Special Thanks goes to: Admirable Persons: Mr. Narayan Parajuli Mr. Laxman Parajuli Advisers: Mr. Dan Bdr. K.C. Principal of Arjun English Boarding High School Tamghas, Gulmi

& Mr. Keshav Parajuli Head of department of science Gulmi

Title

:

A Text Book of Practical Science

Publisher

:

ASIA PUBLICATIONS PVT. LTD.

Bagbazar, Kathmandu Author Edition © Computer Type Computer Setting & Design

: : : : :

Tel: 4232879, 4239174, 4257462 Fax. 4239190 Writer First– 2012 A.D. Publisher Kulchandra, Pradip Parajuli & Suma Poudel Asia computer Section

Price : Rs.180/–

iii

Preface Our world has witnessed great changes and development in the last few decades. Today, everyday is a day of new discovery, invention and achievement in the field of science and Technology. These discoveries, inventions and achievements are the results of practical education. This book is an attempt to present the subject in a special way, because it was felt that competent material to explain the subject was somewhat found lacking in the market. It is hoped that the shortage, or rather the need, will be fulfilled. This book 'A Textbook of practical Science' has evolved as an outcome of a long time classroom teaching experience of the authors. The contents of this book have been presented in accordance with the needs of the students as well as the teachers. So, the authors believe that it is a complete book required for the syllabus prescribed by curriculum development centre (CDC). This book is expected to deserve a significant result because of the following special features:  Correct and lucid explanation of the way to perform experiment.  Scientific explanation of the experiment by theory and Interpretation which helps students to understand the laws related to the experiment.  All the materials are accessible in the simple lab required to perform experiment which are explained in this book.  Way to write experiment with practical copy.  Syllabus provided by CDC with Model Question and Marking Scheme.  Prepared accordance with the syllabus issued by CDC.  Viva questions related to each and every experiment are included. Guide lines for Teachers and Students  All the science teachers are requested to spend at least 1 day per week in lab.  Explain all the information and principles regarding the experiment before performing that experiment.  To perform project work, all the students of the class must be divided into different group of about 5 students. This book is a result of a long inspiration and moral support of many visible and invisible persons. We are grateful to all of them. We are thankful to Mr. Sachin iv

Pandey (Bro). Mr. Arjun Acharya, Mr.Jagat Psd.Pandey & Mr. Binaya Banjade for their co-operative suggestions and help. At last, heartily thanks to Mr. Nabnidhi Pant of Asia publication for publishing this book and both Himal G. C., Kumar Dulal for their attractive layout designing of this book. We have tried our best to avoid errors in the presentation of contents, and we are entirely responsible for the errors, if any, found in the book. We will be thankful to all the readers who point out the weakness and provided us with suggestions for the improvement of the book. Authors

v

Instruction for the students to write Experiment: 

After performing experiment in the lab write all the Experiment in your practical copy systematically (Provided with this textbook).



No need to write Procedure for the experiment of Physics and Chemistry.



Write the experiment only on one side of the copy and draw figures on the drawing page provided on the left side.



Write comments on the right page of the copy after drawing figure in Biology.



Get information related to the practical by reading VivaQuestions.



At least 30 experiments must be performed in the lab within



Submit the experiment and get signed from your Science

one academic session. teacher. 

Fill the experiment and date on the table provided in this book and get signed from your Science teacher.

vi

CONTENTS Expt.No.

Name of the Experiment

Page No.

PHYSICS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24.

1–43

To study the relation between the Pressure exerted by liquid with depth. To study Pascal’s Law in Laboratory. To determine the Upthrust of given liquid. To study the relation between Upthrust and Density of liquid. To Study the relationship between Upthrust given by any liquid and volume of object. To study Archimedes's Principle in Laboratory. To study the Law of Floatation. To study the relation between Mass and change in Temperature. To study the relation between Specific heat capacity and change in Temperature of any object. To study the Nature of the rays refracted from convex and concave lens. To study the Nature & Position of image formed by convex lens when object is placed beyond 2F by using ray diagram and find Magnification. To study the Nature & Position of image formed by convex lens when object is placed at 2F by using ray diagram and find Magnification. To study the Nature & Position of image formed by convex lens when object is placed in between F and 2F by using ray diagram and find Magnification. To study the Nature & Position of image formed by convex lens when object is placed at F by using ray diagram and find Magnification. To study the Nature & Position of image formed by convex lens when object is placed in between F and O by using ray diagram and find Magnification. To study the nature of position of image formed by Concave lens when object is placed in between infinity and Focus. To study the Nature of Position of Image formed by Concave lens when object is at Infinity. To study Shortsightedness defect of Human Eye & way to remove it by preparing a model of short sighted eye. To study Long sightedness defect of Human Eye & way to remove it by preparing a model of short sighted eye. Project Work: To prepare a model of Terrestrial Telescope. To study the Series & Parallel combination of Cells. Project Work: To prepare a Model of Series & Parallel combination of bulbs. To study the Magnetic effect of current by using Compass Needle. To study the Magnetic Field of any conductor when electricity is passed through it.

vii

1 2 2 3 4 5 7 9 11 14 15 17 18 20 21 23 24 26 27 28 30 32 33 34

25. 26. 27. 28. 29.

To Prepare Electromagnet in Laboratory. To study the Electrolysis of Water. To study the Electroplating of Copper on Iron. To study the Electromagnetic Induction in Laboratory. Project Work: To Prepare a Model of Electric Bell in Laboratory.

Viva Questions

40

Chemistry 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40.

44 45 47 48 49 50 51 55 56 57 59

Viva Questions

59

To Study the different parts of Compound Microscope

42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53.

44–60

To study the relation between Rate of Reaction and Concentration of Reactants. To study the relation between Rate of Reaction and Temperature To study the Reaction–Burning of Magnesium ribbon in Air. To identify Acid, Base and Salt. To study the Hard and Soft Acid in the Laboratory. To measure the pH value of Soil. To study the Neutralization Reaction in Laboratory. To prepare Carbon Dioxide gas in Laboratory. To prepare Ammonia gas in the lab. To prepare Soap in the Laboratory. To collect different Metals around the school.

Biology Astronomy and Geology

41.

35 36 37 38 39

61–91 61

To study the Museum Specimen of following organisms and classify with one diagnostic character To observe the following Organism and classify it with one characteristic. To observe the Permanent slide of the following Organism and classify with one character. To observe the permanent slide of To draw the fig of reproduction of Amoeba,Spirogyra and Hydra. To study Mitosis cell division by using Permanent slide. To study Meiosis cell division by using Permanent slide. To draw the lifecycle of Fern To draw the life cycle of Mushroom To draw the fig of Neuron of Human Beings. To draw the figure of Human Heart. Project Work: To prepare a model of Mitosis and Meiosis cell division. A Sample of Excursion Report:

77 78 79 80 80 81 82 83 83 84 85

Viva Questions Specification grid & Model Questions Experimental Sheet

88 91

62 70

86

viii

P  Experiment No.1 To study the relation between the Pressure exerted by liquid with depth. Materials Required:  A tin can with three holes within a vertical line.  Water  Tripod stand Theory: The pressure exerted by liquid in any vessel is given as, P = hdg Where, P = pressure, h = depth of liquid column, d = density of liquid and g = acceleration due to gravity Procedure:  Take a tin can with three side holes A, B Fig.: Water Coming from different holes and C at different heights as shown in the fig.  Close the holes A, B and C  Fill the can with water.  Open these holes A, B and C simultaneously.  Observe the Pressure of liquid coming from each hole. Interpretation: In the above experiment depth of hole C is greater than other so pressure of liquid coming from C is large. Conclusion: From the above experiment it is found that the Pressure exerted by liquid increases with increase in depth. Precaution:  The size of all three holes must be same.  The depth of three holes must be different.  Three holes must be opened simultaneously Class-10 Practical Science 1

Experiment No.2 To study Pascal’s Law in Laboratory.

Materials Required:  Plastic Bag  Pin or needle  Water Theory: Pascal’s law states that, when pressure is applied on a liquid enclosed in a vessel, it is transmitted equally in all the direction. Procedure:  Take a polythene bag and fill it with

  

water and close its mouth with a Fig.: Verification of pascal Law piece of thread. Hold this polythene bag gently where it is tied by thread. Make many holes of same size at the same height with the help of needle. And apply force slowly to the bag. Observed the water coming out through these different holes.

Interpretation: Since the height of all the holes is same water comes out with same pressure. Conclusion: From the above experiment it is found that the pressure exerted by the liquid is same in all the direction at the same height. Precaution:  Reasonable plastic bag with water must be taken.  Bag must be hold at the paint where it is tied.  Holes must be equal in size and at the same height.  Bag must be forced slowly. Experiment No.3 To determine the Upthrust of given liquid. Materials Required: 2

Physics

   

Stone Spring balance Beaker Thread

Theory: Upthrust given by any liquid is defined as the resultant upward force given by the liquid when any object is placed in it. Mathematically, Upthrust = weight of object in air weight of object in Liquid

Fig.: Measurement of Upthrust.

Procedure:  Take a beaker containing sufficient amount of water.  Take a stone and tie it through thread.  Take weight of stone using spring balance in air.  Take the weight of stone after placing in the water.  Fill the table below by above readings. Observation Table: Weight of stone in air (W1)

Weight of stone in liquid (W2)

Upthrust ( F = W1-W2)

Result: From the above experiment it is found that the Upthrust of given liquid is…………. Precaution: 

Stone must be of suitable size.



Sufficient amount of water must be taken such that the stone can be dipped freely.



Readings must be taken carefully.



The stones must not touch the bottom while weight is taken.

Experiment No.4 To study the relation between Upthrust and Density of liquid.

Materials Required: Class-10 Practical Science 3

   

Beakers (2) Egg(2) Salt Water

Theory: Upthrust is the resultant upward force given by liquid when any object is placed on it. Mathematically it is given as F = dgv Where F = Upthrust , d = Density of liquid , v = Volume of object . The above relation shown that Upthrust is directly proportional to Fig.: Sinking and floatation of egg. the density of the liquid. Procedure:  Take two beakers A and B. And fill them with water.  Add salt in the beaker B and make density of liquid relatively large then that of beaker A.  Keep an egg in each beaker.  Observe the position of egg in each beaker i.e. sinking of egg in beaker A and floating in baker B. Interpretation: Since the density of liquid in beaker A is greater than in beaker B so egg sinks in beaker A. Result: From the above experiment it is found that the Upthrust directly proportional to the density of the liquid.

given by any liquid is

Precaution:   

Take care while putting salt i.e. the density of two liquid must be relatively different. The eggs must be well. Eggs must be placed gently.

Experiment No.5 To Study the relationship between Upthrust given by any liquid and volume of object.

4

Physics

Materials Required:  Stones (Two different )  Spring balance  Thread  Beaker with water Theory: Upthrust is the resultant upward force given by any liquid when any object is placed on it. Mathematically it is given as F = dgV Where F = Upthrust , D = density of liquid , V = Value of object This shows that the Upthrust given by any liquid is directly proportional to the volume of the object placed in it. Procedure: Take a beaker containing sufficient amount of water.  Take two stones in which mass of one is double of another.  Tie one stone by thread and take its weight by using spring balance.  Put that stone in water and take weight.  Repeat the above steps for next stone and fill the table blow. Observation Table: S.N 1. 2.

Weight of stone in air (W1)

Weight of stone in air (W1)

Upthrust ( F = W1-W2)

Interpretation: Since the volume of 2nd stone is greater than 1st, Upthrust experienced by 2nd stone is greater. Conclusion: From the above experiment it is found that the Upthrust given by any liquid is directly proportional to the volume of object placed in it. Precaution:  Two relatively different stones must be taken.  The stone must not touch the bottom while taking weight. Experiment No. 6 To study Archimedes's Principle in Laboratory. Class-10 Practical Science 5

Materials Required:  Spring balance  Overflow can  Pan balance  Stone  Thread Theory: Archimedes's principle states that, "When a body is partially or wholly immersed in a liquid it experience an Upthrust which is equal to the weight of displaced liquid". This principle gives measurement of Upthrust. Fig.: Verification of Archimedes Principle

Procedure:  Take an overflow can filled with the liquid up to the level of overflow.  Put a beaker above a pan balance. Such that over flow liquid will directly fall on it.  Take a stone tied by thread and take its weight (W1) using spring balance.  Note the weight (W3) of beaker by using pan balance.  Put the stone in an overflow can gently and take its weight (W2)  When stone is placed in water the over flowed water flows to the beaker.  Take the weight w4 of beaker and water with displaced liquid.  Find the (W1- W2) and compare its value with (W4-W3), result must be same and fill the table below.

Weight of the stone in Air (W1)

Weight of the stone in liquid (W2)

Weight of beaker (W3)

Weight of beaker with water (W4)

Upthru st F= W1W2

Weight of displaced liquid W= W4- W3

Remarks

Observation Table:

F=W

Result: From the above experiment it is found that the Upthrust experienced by any object is equal to the weight of displaced liquid.

6

Physics

Precaution:   

The stone must be placed slowly and gently. Stone must not touch the bottom of beaker. Weight must be taken carefully.

Experiment no.7 To study the Law of Floatation. Materials Required:  Overflow can  Beaker  Pan balance  Spring balance  Tripod stand  Wooden block [ 3 different ] Theory: Law of floatation states that," The weight of floating body is equal to the weight of liquid displaced by it".

Fig.: Verification of Principle of floatation

Procedure:  Take an overflow can fill with water up to the level of spout (overflow).  Take a first wooden block and measure its weight (W1) by using spring balance.  Take a beaker and put above a pan balance and measure its weight (W2).  Put this wooden block in the overflow can so that some amount of water will pass from can to beaker.  Take the weight of breaker with displace water (W3).  Calculate (W3-W2) and compare its value with W1.  Repeat the above steps for other two wooden blocks also. Observation Table: S.N

Weight of wooden blocks (W1)

Weight of beaker (W2)

Weight of beaker with water (W3)

W3-W2

Remarks

Class-10 Practical Science 7

1. 2. 3.

W3-W2 = W1

Result: From the above experiment it is found that the weight of any floating body is equal to the weight of displaced liquid. Precaution:  The wooden block of suitable size must be taken.  The weight must be taken carefully.  The beaker must be taken just below the spout.  The wooden block must be placed gently. 

Viva Questions Pressure 1.

Define pressure.  Force per unit area acting perpendicularly.

2.

What is the SI and CGS unit of pressure?  SI unit= N/m2 and CGS unit = Dynes/cm2

3.

Define 1 pascal.  Pressure exerted by 1 N force in 1 m2 area.

4.

What are the factors on which liquid pressure depends?  Height of liquid column, density of liquid and acceleration due to gravity

5.

State Pascal's Law.  When pressure is applied on a liquid enclosed in a vessel, it is transmitted equally in all the direction

6.

What is the unit of density in SI and CGS unit?  CGS unit gm/cm3 and SI unit kg/m3

7.

What is the density of water in SI and CGS unit?  1gm/cm3 and 1000 kg/m3

8.

What is the formula of relative density?  Relative density = Fehler!

9.

8

What is the meaning that relative density of ice is 0.9? Physics

 The density of ice is 0.9 times the density of water at 4oc 10.

Write the names of instrument which are based upon Pascal.  Hydrolic press, Hydrolic Brake, Hydrolic lift.

11.

Define Upthrust.  Resultant upward force given by any fluid.

12.

Define density.  Mass per unit volume is called density.

13.

Write down the formulae of up thrust.  Upthrust = weight of object in air weight of object in Liquid

14.

Which liquid water or oil gives more Upthrust? Why?  Oil as it has high density.

15.

State Archimedes Principle.  When a body is partially or wholly immersed in a liquid it experience an Upthrust which is equal to the weight of displaced liquid

16.

State the principle of floatation.  The weight of floating body is equal to the weight of liquid displaced by it".

17.

Write down the instrument of floatation which are based upon floatation  Hydrometer, Lactometer etc

18.

What is Hydrometer?  Device which is used to measure relative density of liquid

19.

What is lactometer?  Device which is used to measure purity of milk

20.

Define acceleration due to gravity.  Acceleration produced during freefall.

21.

What is the use of hydrolic brake?  To stops the vehicles.

22.

What is the condition of floatation?  Density of object less than that of liquid. If the weight of displaced is equal to the weight of body.

23.

What is the value of g in SI and CGS unit?  On earth surface the value of g is 9.8 m/s2 and 980 cm/s2

Experiment No.8 To study the relation between Mass and change in Temperature. Class-10 Practical Science 9

Materials Required:  Two identical beaker  Two identical sprit lamp  Two stands  Two thermometer  Water  Stopwatch Theory: According to the heat equation the change in temperature of any substance depends upon the mass and the heat energy supplied i.e. dQ = M S dT Or,

dT = Fehler! Where,

dT = Change in temperature Fig.: Heating of Water dQ = Heat energy supplied M = Mass of substance S = Specific heat capacity I.e. if equal amount of heat energy is supplied the temperature of body with less mass will be higher.

Procedure:  Take two identical beakers.  Fill one beaker with 50ml of water and another with 100 ml of water.  Set up the apparatus as shown in figure.  Take the initial temperature of mixture by using thermometer.  Heat the beaker with sprit lamp.  Observe the final temperature.  Find the difference in temperature and fill the table below. Observation Table: S.N. Volume of water (V) Initial temperature (T1) 1 50 ml

10 Physics

Final temperature (T2) Difference(T2-T1)

2

100 ml

Interpretation: In the above experiment since the mass of water in 1st beaker is less than the mass in 2nd beaker difference in temperature in 1st beaker is large. Conclusion: From the above experiment it is found that if equal amount of heat energy is supplied to two bodies containing different mass the change in temperature of body with less mass in higher. Precaution:  Beakers and sprit lamps must be identical.  Beakers must be heated for exactly same time.  Temperature must be noted carefully. Experiment No.9 To study the relation between Specific heat capacity and change in Temperature of any object. Materials Required:  Beaker (two)  50 ml water and 50 gm sand  Sprit lamp (two)  Stand (two)  Thermometer (two)  Stopwatch Theory: When any object is heated its temperature rises and vice versa. Specific heat capacity of any substance is defined as the amount of heat energy required to change the temperature of 1kg of any substance through 1oc. The heat equation is dQ = M S dT dT = Change in temperature dQ = Heat energy supplied

Fig.: Heating of water and Sand

Class-10 Practical Science 11

M = S =

Mass of substance Specific heat capacity

From above, dT Fehler!i.e change in temperature of any object having less specific heat capacity in more & vice versa.

Procedure (For Table 1) 

Take two beakers.



Put 50ml of water in beaker A and 50mg of sand is beaker B.



Fix the thermometer as shown in figure.



Take two identical sprit lamps.



Take initial temperature of both liquids.



Start to heat the beaker and stop watch simultaneously.



Heat the beaker until the change in temperature is 50C.



Stop the stopwatch & sprit lamp suddenly when the temperature change is 50C.



Note the final temperature and time taken to increases temperature.

For Table 2: 

Take both liquid at the same Temperature fitted with the thermometer as shown in the figure and start stop watch.



Cool freely in the atmosphere until the temperature change in 50C for both liquid.



Note the time taken and fill the table below:

Observation Table: (Table 1) S.N

Initial temperature (T1)

Final temperature

Change in temperature

(T2)

(dT=T2-T1)

Time taken

1. 2. Table 2 S.N

Initial

Final

Change in temperature

temperature (T1)

temperature (T2)

(dT=T1-T2)

Time taken

1. 2.

Interpretation: Since the specific heat capacity of water is more than sand, time taken by water to 12 Physics

change 50C is more.

Conclusion: From the above experiment it is found that the time taken to change the temperature by any object having high specific heat capacity is more than that of low specific heat capacity. Precaution: a. Two substances having relatively different specific heat capacity must be taken. b. Sprit lamp must be identical. c. Time and Temperature must be noted carefully.

Viva questions Heat and Temperature 1.

Define heat and temperature.  Total sum of kinetic energy of all the molecules is called heat where as the average K.E of the molecule is temperature.

2.

What is the unit of heat in SI unit and CGS unit?  SI unit- joule CGS unit-ergs 1 joule= 107 ergs.

3.

What is the unit of temperature in SI unit?  Kelvin.

4.

Write relation between different temperature scales.  Fehler!= Fehler!= Fehler!= Fehler!

5.

What is the relation of Joule and calorie?  4.2 J=1 calorie

6.

What is the temperature of healthy person?  370c or 98.60F or 310 K

7.

At what temperature water has highest density?  40c

8.

Which devices are used to measure Heat and temperature?  Heat = calorimeter Class-10 Practical Science 13

Temperature = thermometer 9.

Write down the Boiling point and Melting point of Mercury and Alcohol  Freezing Boiling Mercury -390c 357oc Alcohol

-1170c

780c

10.

What is upper fixed point?  Upper fixed point of any thermometer is the temperature of pure boiling water or steam at normal pressure (760mmof Hg).

11.

What is lower fixed point?  Lower fixed point of any thermometer is the temperature of melting ice at normal pressure (760mmof Hg).

12.

When two bodies of unequal masses are heated by same amount of heat energy whose temperature will be high?  Object having less mass On which factors does heat energy depends?  Number of molecules and kinetic energy of each molecule

13. 14.

What is specific heat capacity?  The amount of heat energy required to change the temperature of 1kg of any substance through 1oC.

15.

Write heat equation.  dQ = M S dT

16.

What is the principle of thermometer?  Liquid expands on heating.

17.

What is the unit of specific heat capacity?  J/kgoc

18.

What is the specific heat capacity of water?  4200J/kgoc

19.

What is the meaning of 4200J/Kgoc specific heat capacity?  4200J heat energy is required to raise the temperature of 1 kg mass by 10c.

20.

What is 1 calorie heat energy?  The amount of Energy required to raise the temperature 1gm of pure water by 1oc

21.

If equal amount of heat energy is supplied to water and sand at same temperature, which one will have high temperature? Why?  Sand as its specific heat capacity is low.

Experiment No.10 14 Physics

To study the Nature of the rays refracted from convex and concave lens.

Materials Required:  Concave lens  Convex lens  Scale  Paper Theory: When a parallel beam of light is incident on a concave lens, the rays are diverges so it is called diverging lens whereas when the light rays are incident on a convex lens they meet at a point after refraction so it is called conversing lens.

Fig.: Convex & Concave Lens

Procedure:    



Take a convex lens and put in a sun light. Put the paper at about the distance of 10cm from the lens. Focus the refracted rays from lens on paper by moving the lens. Move the lens away from the paper and get smallest ring of light and keep this for sometime so that paper starts to burn. Take concave lens and do the above steps, the small ring cannot be observed and the paper doesn't burn.

Conclusion: From the above experiment it is found that the light rays refracted from convex lens are converged where as the light rays refracted from concave lens are diverged. Precaution:  Paper should be kept at about the distance of 10cm from the lens.  Light must be converged carefully. Experiment No.11 To study the Nature & Position of image formed by convex lens when object is placed beyond 2F by using ray diagram and find Magnification. Materials Required: Class-10 Practical Science 15

   

Convex lens Paper Pencil Scale

Theory: When a beam of light is incident on a convex lens the rays are converged. When object is placed beyond 2F the image is formed on other side of lens between F and 2F with the following characteristic:  Real  Inverted  Smaller in size Magnification is defined as the ratio of size of the image to the size of Fig.: Ray diagram of a convex lens when the object and it is given as , object is placed beyond 2 F = Magnification (M) Fehler! = Fehler! I.e. M = Fehler! = Fehler!

Procedure:  Take a convex lens and a sheet of paper.  Make a figure of convex lens on the centre of paper and remove lens from the paper.  Draw an optical axis of the Lens.  Draw a long principle axis more than 10cm perpendicular the to the optical line  Indicate the focus (F) at the distance of 2cm from optical center on both side of lens.  Fix 2F at the distance of 4cm.  Put the object beyond 2F by an upward arrow AB.  Draw a parallel line to the principle axis from the top of object to the lens.  Join this line from top of lens with focus and produce long.  Draw a line joining top of object and optical centre and produce it.  Draw a normal from intersecting point to the principle axis i.e. A'B'. This is the image of the object AB.  Measure the distance of object (AO) and distance of image (A'O) and fill the table below and find Magnification. Observation Table: Object distance (u=AO)

Conclusion: 16 Physics

Image distance (v=A'O)

Magnification (M = Fehler!)

From the above experiment it is found that the nature of image formed by Convex lens when object is placed beyond 2F are  Image is Real, Inverted  The image is formed in between F and 2F on other side of the lens.  Magnification < 1.

Precaution:  Pencil must be sharp.  Distance must be measured carefully.  Arrows must be given for the rays. Experiment No.12 To study the Nature & Position of image formed by convex lens when object is placed at 2F by using ray diagram and find Magnification. Materials required:  Convex lens  Paper  Pencil  Scale Theory: When a beam of light is incident on a convex lens the rays converged when object is placed at 2F the image is formed on other side of the lens at 2F with the following characteristics :Fig.: Ray diagram of Convex lens when  Real object is placed at 2 F  Inverted  Same size Magnification is defined as the ratio of size of the image to the size of the object and it is given as , Magnification (M) = Fehler! = Fehler! I.e. M = Fehler! = Fehler! Procedure:  Take a convex lens and a sheet of paper.  Make a figure of convex lens on the centre of paper and remove lens from the paper.  Draw an optical axis of the Lens.  Draw a long principle axis more than 10cm perpendicular the to the optical axis. Class-10 Practical Science 17



Indicate the focus (F) at the distance of 2cm from optical centre on both side of lens.



Fix 2F at the distance of 4cm.



Put the object at 2F by an upward arrow AB.



Draw a parallel line to the principle axis from the top of object to the lens.



Join this line from top of lens with focus and produce long.



Draw a line joining top of object and optical centre and produce it.

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Draw a normal from intersecting point to the principle axis i.e. A'B'. This is the image of the object AB.

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Measure the distance of object (AO) and distance of image (A'O) and fill the table below and find Magnification.

Observation Table: Object distance (u =AO)

Image distance ( =A'O)

Magnification ( = Fehler!)

Conclusion: From the above experiment it is found that the nature of image formed by Convex lens when object is placed at 2F are  Image is Real, Inverted  The image is formed in at 2F on other side of the lens.  Magnification = 1. Precaution:  Pencil must be sharp.  Distance must be measured carefully.  Arrows must be given for the rays. Experiment No.13 To study the Nature & Position of image formed by convex lens when object is placed in between F and 2F by using ray diagram and find Magnification. Materials required:  Convex lens  Paper  Pencil  Scale Theory: When a beam of light is incident on a convex lens the rays are converged. When object is

18 Physics Fig.: Ray diagram of convex lens when object is placed in between F and 2 F.

placed in between F and 2F, the image is formed on other side of the lens beyond 2F with the following characteristics : Real  Inverted  Large size Magnification is defined as the ratio of size of the image to the size of the object and it is given as , Magnification (M) = Fehler! = Fehler!I.e. M = Fehler! = Fehler!

Procedure:  Take a convex lens and a sheet of paper.  Make a figure of convex lens on the centre of paper and remove lens from the paper.  Draw an optical axis of the Lens.  Draw a long principle axis more than 10cm perpendicular the to the optical axis.  Indicate the focus (F) at the distance of 2cm from optical centre on both side of lens.  Fix 2F at the distance of 4cm.  Put the object in between F and 2F by an upward arrow AB.  Draw a parallel line to the principle axis from the top of object to the lens.  Join this line from top of lens with focus and produce long.  Draw a line joining top of object and optical centre and produce it.  Draw a normal from intersecting point to the principle axis i.e. A'B'. This is the image of the object AB.  Measure the distance of object (AO) and distance of image (A'O) and fill the table below and find Magnification. Observation Table: Object distance (u = AO)

Image distance ( = A'O)

Magnification (M = Fehler!)

Conclusion: From the above experiment it is found that the nature of image formed by Convex lens when object is placed in between F and 2F is  Image is Real, Inverted  The image is formed beyond 2F on other side of the lens.  Magnification >1. Precaution:  Pencil must be sharp.  Distance must be measured carefully.  Arrows must be given for the rays.

Class-10 Practical Science 19

Experiment No.14 To study the Nature & Position of image formed by convex lens when object is placed at F by using ray diagram and find Magnification. Materials required:  Convex lens  Paper  Pencil  Scale Theory: When a beam of light is incident on a convex lens the rays are converged. When object is placed at F, the image is formed at infinity with the following characteristics:Fig.: Ray diagram of Convex lens when  Real object is placed at F  Inverted  Highly magnified Magnification is defined as the ratio of size of the image to the size of the object and it is given as, Magnification (M) = Fehler! = Fehler! I.e. M = Fehler! = Fehler!

Procedure:  Take a convex lens and a sheet of paper.  Make a figure of convex lens on the centre of paper and remove lens from the paper.  Draw an optical axis of the Lens.  Draw a long principle axis more than 10cm perpendicular the to the optical axis.  Indicate the focus (F) at the distance of 2cm from optical centre on both side of lens.  Fix 2F at the distance of 4cm.  Put the object at F by an upward arrow AB.  Draw a parallel line to the principle axis from the top of object to the lens.  Join this line from top of lens with focus and produce long.  Draw a line joining top of object and optical centre and produce it.  Observe two parallel rays forming image at infinity.  Measure the distance of object “O and distance of image as infinity ∞ and fill the table below and find Magnification. Observation Table: Object distance (u=AO)

20 Physics

Image distance (v=A'O)

Magnification (M = Fehler!)



Conclusion: From the above experiment it is found that the nature of image formed by Convex lens when object is placed at F is  Image is Real, Inverted  The image is formed at infinity on other side of the lens.  Magnification = ∞. Precaution:  Pencil must be sharp.  Distance must be measured carefully.  Arrows must be given for the rays. Experiment No.15 To study the Nature & Position of image formed by convex lens when object is placed in between F and O by using ray diagram and find Magnification. Materials required:  Convex lens  Paper  Pencil  Scale Theory: When a beam of light is incident on a convex lens the rays are converged. When object is placed in between F and O, the image is formed on the same side Fig.: Ray diagram of Convex lens when object of the Lens with the following is placed in between F and 2 F characteristics: Virtual  Erect  Highly magnified Magnification is defined as the ratio of size of the image to the size of the object and it is given as, Magnification (M) = Fehler! = Fehler! I.e.M = Fehler! = Fehler!

Procedure: Class-10 Practical Science 21

            



Take a convex lens and a sheet of paper. Make a figure of convex lens on the centre of paper and remove lens from the paper. Draw an optical axis of the Lens. Draw a long principle axis more than 10cm perpendicular the to the optical axis. Indicate the focus (F) at the distance of 2cm from optical centre on both side of lens. Fix 2F at the distance of 4cm. Put the object in between F and O by an upward arrow AB. Draw a parallel line to the principle axis from the top of object to the lens. Join this line from top of lens with focus and produce long. Draw a line joining top of object and optical centre and produce it. Observe two diverging rays. Produce these rays back and get intersecting rays. Draw a normal from intersecting point to the principle axis i.e. A'B'. This is the image of the object AB. Measure the distance of object (AO) and distance of image OA' and fill the table below and find Magnification.

Observation Table: Object distance (u = AO)

Image distance (v = A'O)

Magnification (M = Fehler!)

Conclusion: From the above experiment it is found that the nature of image formed by Convex lens when object is placed in between F and O is  Image is Virtual, Erect  The image is formed on the same side of the lens.  Magnification >>>1. Precaution:  Pencil must be sharp.  Distance must be measured carefully.  Arrows must be given for the rays. Experiment No. 16 To study the nature of position of image formed by Concave lens when object is placed in between infinity and Focus. Materials Required:  Concave lens 22 Physics

  

Pencil Scale Paper

Theory: When a beam of light is incident on a concave lens the rays are diverged. When object is placed in between infinity and focus the image is formed on the same side of lens in between F & O with the following characteristic : Virtual Fig.: Ray diagram of Concave lens when  Diminished object is placed in between F & Infinity  Erect Magnification is defined as the ratio of size of the image to the size of the object and it is given as, Magnification (M) = Fehler! = Fehler! I.e. M = Fehler! = Fehler!

Procedure:  Take a concave lens and a paper.  Draw the figure of concave lens on the centre of paper and remove that lens.  Draw optical axis & the long principle axis (More than 10cm) to the optical axis.  Indicate the focus F at the distance of 2cm from the optical centre on both sides of the lens.  Fixed 2F at the distance of 4cm on the both sides of lens.  Put the object beyond F by an upward arrow AB.  Draw a parallel line to the principle axis from the top of the object to  Draw the diverging line from lens and produce it back such that it must intersect at F.  Draw a line joining top of object and optical centre and produce it back.  Draw a normal from intersecting point to the principle axis i.e. A'B'. This is the image of object AB.  Measure the distance of object (AO) and distance of image A'O and fill the table, and find Magnification. Observation Table: Object distance(u) = AO

Image distance (v) = A'O

Magnification M = Fehler!

Conclusion: Class-10 Practical Science 23

From the above experiment it is found that the nature of the image formed by concave lens when object is placed in between infinity and focus is:  Erect and virtual  The image in formed in between F and O.  Magnification m