Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

It becomes possible to define potential at a point in an electric field because electric field:

The penetrating power of X-rays depends upon :

If a rod has resistance 4 W and if rod is turned as half cycle then the resistance along diameter

(a) 1.56 W

(b) 2.44 W

(c) 4 W

(d) 2 W

A torch bulb rated as 4.5 W, 1.5 V is connected as shown in the figure. The e.m.f. of the cell needed to make the bulb glow at full intensity is

(a) 4.5 V

(b) 1.5 V

(c) 2.67 V

(d) 13.5 V

The wavelength of emission line spectrum and absorption line spectrum of a substance are related as

(a) Absorption has larger value	(b) Absorption has smaller value
(c) They are equal	(d) No relation

A piece of wire of resistance 4 ohms is bent through 180°  at its mid point and the two halves are twisted together, then the resistance is

(a) 8 ohms

(b) 1 ohm

(c) 2 ohms

(d) 5 ohms

When charged particle enters-a uniform magnetic field, its K.E:

When the electron in the hydrogen atom jumps from 2^nd orbit to 1^st orbit, the wavelength of radiation emitted is 𝜆. When the electrons jump from 3^rd orbit to 1^st orbit, the wavelength of emitted radiation would be

(a)

(b)

(c)

(d)