Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

When electron beam passes through an electric field, they gain kinetic energy. If the same beam passes through magnetic field, then

(a) Their energy increases

(b) Their momentum increases

(c) Their potential energy increases

(d) Energy and momentum both remains unchanged

Materials which allow only larger currents to flow through them are:

In a full wave rectifiers, input ac current has a frequency ‘n’. The output frequency of current is

(a) n/2

(b) n

(c) 2n

(d) None of these

Figure shows two capacitors connected in series and joined to a battery. The graph shows the variation in potential as one moves from left to right on the branch containing the capacitors:

A point charge is kept at the centre of a metallic insulated spherical shell. Then

(a) Electric field out side the sphere is zero	(b) Electric field inside the sphere is zero
(c) Net induced charge on the sphere is zero	(d) Electric potential inside the sphere is zero

Unit of magnetic flux density (or magnetic induction) is

(a) Tesla	(b) Weber/metre2
(c) Newton/ampere-metre	(d) All of the above

A 20cm long capillary tube is dipped in water. The water rises up to 8cm. If the entire arrangement is put in a freely falling elevator, the length of water column in the capillary tube will be:

1. 8cm
2. 6cm
3. 10cm
4. 20cm

+q, +2q, +3q, +4q, ……(up to +20q) charges are situated at coordinates (0, 0), (1, 0), (2, 0), ….. (Up to 20). What is the total charge stored in the system?