Semiconductor Electronics: Materials, Devices and Simple Circuits — Physics STD 12 Science — Question

In a YDSE bi-chromatic light of wavelengths 400 nm and 560 nm are used. The distance between the slits is 0.1 mm and the distance between the plane of the slits and the screen is 1m. The minimum distance between two successive regions of complete darkness is

(a) 4 mm

(b) 5.6 mm

(c) 14 mm

(d) 28 mm

The mass of a neutron is the same as that of

(a) A proton

(b) A meson

(c) An epsilon

(d) An electron

Out of the following statements which is not correct

(a) When unpolarised light passes through a Nicol's prism, the emergent light is elliptically polarised

(b) Nicol's prism works on the principle of double refraction and total internal reflection

(c) Nicol's prism can be used to produce and analyse polarised light

(d) Calcite and Quartz are both doubly refracting crystals

The velocity of a particle is zero at t = 0.

1. The acceleration at t = 0 must be zero.
2. The acceleration at t = 0 may be zero.
3. If the acceleration is zero from t = 0 to t = 10s, the speed is also zero in this interval.
4. If the speed is zero from t = 0 to t = 10s the acceleration is also zero in this interval.

The refractive index of water is 1.33. What will be the speed of light in water

(a) 3

(b) 2.25

(c) 4

(d) 1.33

The mass of a photo electron is

(a) 9.1

(b) 9.1

(c) 9.1

(d) 9.1

The load voltage is approximately constant when a zener diode is:

In order to increase the sensitivity of a moving coil galvanometer, one should decrease

(a) The strength of its magnet	(b) The torsional constant of its suspension
(c) The number of turns in its coil	(d) The area of its coil

A man can see the objects upto a distance of one metre from his eyes. For correcting his eye sight so that he can see an object at infinity, he requires a lens whose power is

(a) + 0.5 D

(b)  + 1.0 D

(c) + 2.0 D

(d)  – 1.0 D

A thermo couple is formed by two metals X and Y metal X comes earlier to Y in Seebeck series. If temperature of hot junction increases beyond the temperature of inversion. Then direction of current in thermocouple will so

(a) X to Y through cold junction	(b) X to Y through hot junction
(c) Y to X through cold junction	(d) Both (b) and (c)