2nd PUC Physics Chapter 1 Electric charge and field important questions for academic year 2023-24

2nd PUC Physics Chapter 1 Electric charge and field important questions for academic year 2023-24

Physics PUC II Important one mark, 2 mark, 3 Marks and 5 Marks most important Questions.

1.mention any one / two properties of electrics charges.

2. What is meant by conservation of charge? Explain.

3. What is meant by quantization of charge? Exaplain.

4. What is meant by additivity of charge. exaplain

5. State and explain coulombus law in electrostatics.

6. Write coulombus law in electrostatics in vector form and explain the symbols.

7. Write the SI unit of charges.

8. Define' coulombs ‘or define the SI unite of charges.

9. How does the electrostatics force between the two point charges change when a electric medium is introduced between them?

10. Define electric field.

11. Mention the SI unit of electric field.

12. Mention an expression for electric field due to a point charge and explain the smymbols.

13. What is an electric dipole?

14. What is an electrc dipole moment?

15. Mention the vectore form of electric dipole moment?

16. mention the SI unit of ekectric dipole moment.

17. What is the net charge of an electric dipole?

18. Mention the expression for torque acting on the electric diploe placed in the uniform electric field.

19. When will be the torque acting on the electric dipole is meximum and minimum?

20. Write the vector form of torque acting on the electric dipole moment?

21. Mention SI unit of torque acting on the dipole placed in the inuform electric field.

22. What are electric field lines?

23. Mention any one/ two properties of electric field lines.

24. Can two electric field lines intersect?

25. What is an electric flux?

26. Mention the SI unit of electric flux?

27. State and explain gauss law in electrics.

28. What is gaussian surface?

29. What is line density of charge?

30. Mention the SI unit of lines density of charge.

31. What is surface denesity of charge?

32. Mention the SI unit surface density of charge.

33. What is value density of charge?

34. Mention the SI unit of volume density of charge?

35. Mention the expression for electrics field n terms of volume density of charge.

36. What is the value of electricle field at a point a inside the charged shell?

37. What is grounding or earthing? What is importance?

38.what is polarity of charge?

39.what is gold leaf electroscope (GLE)?

40. What is the physical singnificance of eletrics field?

41. What is the physical significance of dipoles?

42. Sketch electrics field lines due to point charge q, if i) q< o and ¡¡) q>o,

 43. Name the apparatus used to detect electric charge on a body?

        3 & 5 marks questions

1. Mention any three/ five properties of electrics charges.

2. State superposition principle for forces. Apply it to find the force on point charge due to system of an point charges.

3. Deduce an expression for the electrics field due to system of an point charges by applying superposition principle.

4. Derive an expression for electric field at a point on the axis of the dipole.

5. Derive an expression for electrice field at point on the equatorial line of the dipole.

6. Derive an expression for torque on an electric dipole placed in uniform electrics field.

7. Sketch an explain the electric field lines of ( a ) positives point charge , ( b) a negative point charge, ( c ) a pair of two equal and opposite point charges, and ( d ) a pair of equal positive point charges.

8. Mention any three / five properties of electric field lines.

9. Obtained an expression for electric field due to outside at charged spherical shell by using gauss law.

10. State gauss law in electrostatics. Obtain an expression for electric field at a point just outside a charged thin spherical shell by using guass law.

11. Obation an expression for electric field due to an infinit

 long striaght uniformly charged write by using guases law

12. Obtaion expression for electric field due to unifortmily charge inifenity plane sheet by using gauss law.

13. How will you show that there are two kinds of charges? Explains with diagrams.

14. What is electrification? Explains.

15. What are conductors and insulaters? Give on example for each.

16. Mention the methods of charging a body.

17. Explain with diagrams, the method of charging two metal spheres by induction.

18. How can you charge a metal sphere positively without tuching it? Explain with diagrams.

19. Explain the constructions and working of gold leaf electroscope with diagrams.

20. Show that coulumbusd law agrees with the newtons third law mention by taking the position vectors of two charges.

21. Define density of field lines? What is the relation between electric field strenght and density field lines?

22. Prove that ½ r2 defendence of electrics field of a point charge is consistent with the concept of electrics field lines.

23. Prove gauses law.

24. Verify guases law

  Question bank given by department of pu education

ANSWERS:

1. What is the cause for seeing tha spark or hearing the crackle when, we take off our synthetic clothers particularly in dry weather?

Ans : descharge of elerctric charges.

2. Which phenomenon is responseble for lightning in the sky during thunder storm?

Ans: discharges of electric charge.

3. We experience a sensation of electrics shock while opening the door of a car or will holding the iron bar of a bus after sliding from our seat. Why?

Ans: due to discharge of electric charge trough our body, which were accumulated due to rubbing of insulating surface.

4. Who discoverd the fact that amber rubbed with wool or silk attracts light objects?

Ans: Thales of miletus.

5. What happenes when insualating surface are rubbed with each other?

Ans: They get charged.

6. How many kinds of electrifications are there in nature?

Ans: two.

7. What is the meaning of the greek word ‘electron ‘ from which the name electricity is coined?

Ans: the name electricity coined from the greek word electron meaning amber

8. How many types of charges exists in nature?

Ans: two

9. What is the nature of force between like charges?

Ans: repulsion

10. What is the nature of force between unlike charges?

Ans: attraction.

11. What would happen when two oppositely and equally charged objects are brought in contact?

Ans: the charges are lot when the charged bodies are brought in contact.

12. Who was named two types of charges positive and negative?

Ans: Benjamin franklin

13. Why does a pair of subjects get electric field on rubbing on each other?

Ans: due to transfer of – charges.

14. What is the causes of electrification of an object?

Ans: charge imbalance.

15. When do we say that an object is charged or electric field?

Ans : if an object possess an electrics charges, it is said to be electric field or charged

16. Name the instrument which detects the charge on an object?

Ans: gold leaf electroscope.

17. What does the dgreee of divergence of gold leaves in gold leaf electrosip indicate?

Ans: ammount if charge.

18. How an object does equire positive charge?

Ans: by removing electrons from a natural objects.

19. How an object does equire negative object?

Ans: by adding electrons at a natural objects.

20. When glass rod is rubbed whith silk, glass rod acquire positive charges. Give reason.

Ans: becauses glass rod losess few electrons.

21. When plastics rod is rubbed with cats fur it acquire negative charges.gi e reason..

Ans: because plastic rod gains extra electrons.

22. Why do erlectrostatics expermintes not work well on humind days?

Ans: due to leakage of charges through the humind air.

23. Why can we not charge metal rod when held in hand and rubbed whith wool?

Ans: The charge on metal rod leak trough ou

r body to the ground.

24. What are electronics conducters?

Ans: these are the substance which allow electronic charges to throughs them easily.

25. What are electric insulators?

Ans: these are the substance which do not allow electric charges to pass trough them.

26. Electric charge can be transfered from one object to the other object using copper wire but not with nylon thread. Give reason.

Ans: because nylon thread is an insulator.

27. Give an example of electric conducter.

Ans: copper.

28. Give an exmple of electric insulater.

Ans: glass.

29. Name the three wires in household electricle

Ans: live, natural and earth.

30. Why do we connect the metal parts of the electricle appliances to the earthing wire?

Ans: to avoid damage to the electricle appliances and injury to the humans.

31. Is pure water a conductore or insulator.

Ans: Insulator

32. What is charging by induction?

Ans: charging a concocter by the charge body without physicall contact between them.

33. When a charged comb is brought near small piece of papper, it attracts the piece. Does the papper become charged when the comb is brought near?

Ans: no

34. What is the nature of charge on an electrons?

Ans: negatives

35. When do we treat charged objects as point charges?

Ans: if the sizes of charged bodies are very small as compared to the distance between them, we treat them as point charges.

36. Write the expression for quantization property of charges.

Ans: q= £ne, where is an a integer and is charge on the electron or proton.

37. What is the nature of charges on proton?

Ans : positive.

38. Name the scientist hwo expeorimentally proved the quntization nature of charge.

Ans: millikan

39. How many ectrons make -1 c of charges?

Ans= 6.25×10(18)

40. A glass rod rubbed with silk loses 10(8) electrobs. What is the charge on glass rod?

Ans= q=ne, q= 10(8) × 1.6 × ×10= 1.6 ×10C.

41. When we do neglect the quantization property of charges?

Ans= at the microscopic level.

        42.two point charges of unkown magnitude and sign are at a distance a part. The electric field is zero between them at a point on the line joining the two charges what can you conclude about the charges?

Ans: the two charges ared of same sign.

42. If the electronsin a metal place such as copper are free to move about, they must often find themselves heanded to word the metal surface. Why do they not keep on going and leave the metal?

Ans: due to coulomb forces between the free electron and other the charges in the metal place.

43. An electron ( charge= ) cerculates around a hulium nucleus ( charge =+2) in a hulium atom. Which particle experts the larger force on the other?

Ans= same force

44. Charges of 10 HC are suprated by certain distance. Which charge replace the other greater force?

Ans: same force

45. How does the electric field at a point vary with distance from a point electric charge?

Ans: iniversely proportional to the square of the distance.

46. How electric field at a point does vary with magnitude of sources charges?

Ans:directly proportional to the magnitude of source charges

47. What is source charges?

Ans: the charge which produces the electrical field, is called a sources charges.

48. What is test charges?

Ans: the charge wich testes the effect of a sources of charges is called tests charges.

49. Who first introduced / invented the concept of electric field estblished between two parallel plates. Where would the electrons exeperience greatest force?

Ans: force is unifortm troghout the field..