Ray Optics and Optical Instruments — Physics STD 12 Science — Question

In the circuit shown, a meter bridge is in its balanced state.  The meter bridge wire has a resistance 0.1 ohm/cm.  The value of unknown resistance X and the current drawn from the battery of negligible resistance is

(a) 6 W, 5 amp

(b) 10 W, 0.1 amp

(c) 4 W, 1.0 amp

(d) 12 W, 0.5 amp

The mass defect per nucleon is called:

Two point charges 10C and -10C are placed at a certain distance. What is the electric potential of their midpoint?

The heating coils rating at 220 volt and producing 50 cal/sec heat are available with the resistances 55Ω,110 Ω, 220 Ω   and 440 Ω. The heater of maximum power will be of

(a) 440 Ω

(b) 220 Ω

(c) 110 Ω

(d) 55 Ω

Carbon resistors are of two types:

Which of the following phenomena cannot be explained by the Huygens' wave theory?

A point object is placed at the centre of a glass sphere of radius 6 cm and refractive index 1.5. The distance of virtual image from the surface of the sphere is

The angular momentum of electron in n^th orbit is given by

(a) nh

(b)

(c) n

(d)

The reading of the ideal voltmeter in the adjoining diagram will be

(a) 4 V

(b) 8 V

(c) 12 V

(d) 14 V