## Archive for June, 2012

### Assignment Physics +1 Class  ### Assignment Physics +2 Class

Assignment  | Class : XII | Sub: Physics

1. Can photons ever have a charge?
2. I.e.m.u = _________ coulomb?
1. Which physical quantity has its S.I. unit as    i. Cm               ii. Vm
2. In a medium the force of attraction between two point electric charges distance ‘d’ apart, is F.? What distance apart should these be kept in the same medium so that the force between them becomes 3F?
1. Name the experiment which established the quantum nature of electric charges?
2. How many electrons are present in one covalent?
3. What is the value of integral of the electric field over closed path?
4. Why Coulomb force is called conservative and how it is central force?.
5. Does the Coulomb force between two point charges depend upon orientation between the two charges?
6. Is coulomb’s law true far atomic and nuclear distance?
7. Can two similarly charged balls attract each other?
8. A charge Q is to be divided into two charges q and Q-q. Far what value of q far which the force between the two charges becomes maximum? [q = Q/2]
9. What is the effect of change of medium on the potential at a point?
10. Two positive point charges 20 microC one 1m apart. Calculate the workdone in bringing them closes to each other by 50cm?
11. Electric dipole moment is a vector quantity why?
12. At what points the electric field intensity due to an electric dipole is parallel to the axis of dipole?
13. What is the direction of electric flux?
14. Which property of capacitance makes it useful in time circuit?
15. Can we give any desired charge to a capacitor?
16. Why metals cannot be used as a dielectric in a capacitor?
17. What meaning would you give to the capacity of a single conductor?
18. An uncharged capacitor is connected to a battery show that half of the energy supplied by the battery as loss as heat while charging the capacitor?
19. If a wire is stretched to double its original length without loss of mass how will the resistivity of the wire be influenced?
20. What is a linear circuit?
21. Are the paths of electrons straight lines between successive collisions (with the positive ions of the metal) in the i) absence of electric field ii) the presence of E.F.
22. A wire is carrying current. It is charges? Why?
23. Some times the balance point in the potentiometer many not be obtained on the wire. Explain.
24. It is easier to start a car engine on a warm day than on a chilly day why?
25. How can you make a potentiometer of given wire length more sensitive using a resistance box?
26. Why do we prefer a potentiometer with a longer bridge wire?