Magnetism And Matter — Physics STD 12 Science — Question

Identify which of the following color light, when passed through a double-slit opening, will produce the widest central band of light on the screen?

In Young's interference experiment, if the slits are of unequal width, then:

Amount of light entering into the camera depends upon

(a) Focal length of the objective lens

(b) Product of focal length and diameter of the objective lens

(c) Distance of the object from camera

(d) Aperture setting of the camera

In the above question, the power lost in the cable during transmission is

(a) 12.5 kW

(b) 6.25 kW

(c) 25 kW

(d) 3.15 kW

To draw maximum current from a combination of cells, how should the cells be grouped

(a) Series

(b)Parallel

(c) Mixed

(d) Depends upon the relative values of external and internal resistance

A coil is wound as a transformer of rectangular cross-section. If all the linear dimensions of the transformer are increased by a factor 2 and the number of turns per unit length of the coil remain the same, the self  inductance increased by a factor of

(a)  16

(b) 12

(c)  8

(d) 4

A metallic resistor is connected across a battery. If the number of collisions of the free electrons with the lattice is somehow decreased in the resistor (for example, by cooling it), the current will:

1. Increase.
2. Decrease.
3. Remain constant.
4. Become zero.

Identify the correct statement about the charges q_1​ and q_2​:

In the process of electrolysis, the current is carried out inside the electrolyte by

(a) Electrons	(b) Atoms
(c) Positive and negative ions	(d) All the above

In the Young’s double slit experiment, for which colour the fringe width is least

(a) Red

(b) Green

(c) Blue

(d) Yellow