Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

An iron rod of volume   and relative permeability 1000 is placed inside a long solenoid wound with 5 turns/cm. If a current of 0.5 A is passed through the solenoid, then the magnetic moment of the rod is

(a) 10

(b) 15

(c) 20

(d) 25

A light rays beam enters from air into water. Out of the following which will not be changed ?

Mark the correct option in impure spectrum:

Energy Bands of three substances are shown in the following figures, where V is valance band and C is conduction band.

These substances respectively are :

The electric field lines are crowded where electric field is:

An electron microscope is superior to an optical microscope in

(a) Having better resolving power	(b) Being easy to handle
(c) Low cost	(d) Quickness of observation

Potential difference between the points P and Q in the electric circuit shown is

(a) 4.5 V

(b) 1.2 V

(c) 2.4 V

(d) 2.88 V

The hottest planet of solar system is

(a) Mars

(b) Mercury

(c) Venus

(d) Pluto

There is an air filled 1 pF parallel plate capacitor. When the plate separation is doubled and the space is filled with wax, the capacitance increases to 2pF. The dielectric constant of wax is

(a) 2

(b) 4

(c) 6

(d) 8

The positive terminal of 12V battery is connected to the ground. Then the negative terminal will be at: