Magnetism And Matter — Physics STD 12 Science — Question

The change in frequency due to Doppler effect does not depend on:

1. The speed of the source.
2. The speed of the observer.
3. The frequency of the source.
4. Separation between the source and the observer.

A dip circle is taken to geomagnetic equator. The needle is allowed to move in a vertical plane perpendicular to the mangetic meridian. the needle will stay in:

The capacity and the energy stored in a parallel plate condenser with air between its plates are respectively    and . If the air is replaced by glass (dielectric constant = 5) between the plates, the capacity of the plates and the energy stored in it will respectively be

(a)

(b)

(c)

(d)

An infinite sequence of resistance is shown in the figure. The resultant resistance between A and B will be, when   and

(a) Infinity

(b) 1 Ω

(c) 2 Ω

(d) 1.5 Ω

A bar magnet is cut into two equal halves by a plane parallel to the magnetic axis. Of the following physical quantities the one which remains unchanged is:

To convert a moving coil galvanometer into voltmeter

When a potential difference V is applied across a conductor at a temperature T, the drift velocity of electrons is proportional to:

Permanent magnets are the substances having the property of:

A potentiometer consists of a wire of length 4 m and resistance 10Ω. It is connected to a cell of e.m.f. 2 V. The potential difference per unit length of the wire will be

(a) 0.5 V/m

(b)  2 V/m

(c)  5 V/m

(d) 10 V/m

Resistances of 6 ohm each are connected in the manner shown in adjoining figure. With the current 0.5 ampere as shown in figure, the potential difference  is

(a) 3.6 V

(b) 6.0 V

(c) 3.0 V

(d) 7.2 V