Atoms — Physics STD 12 Science — Question

For the stability of radiated nucleus:

Mass number is:

In an oscillating system, a restoring force is a must. In an L-C circuit, the restoring force is provided by a/ an.

The relative atomic masses of many elements are not whole numbers because:

A parallel plate capacitor having a plate separation of 2 mm is charged by connecting it to a 300 V supply. The energy density is

(a) 0.01 J/m3

(b) 0.1 J/m3

(c) 1.0 J/m3

(d) 10 J/m3

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 capacitor is charged by a battery and then the battery is disconnected. A dielectric slab is introduced between the plates. The result is:

Wavelength of, monochromatic light is 5000A˚. It's wave number is:

The slopes of anode and mutual characteristics of a triode are 0.02 mA V^–1 and 1 mA V^–1 respectively. What is the amplification factor of the valve

(a) 5

(b) 50

(c) 500

(d) 0.5