Atoms — Physics STD 12 Science — Question

Weber/m²  is equal to

(a) Volt

(b) Henry

(c) Tesla

(d) All of these

Hydrogen atom excites energy level from fundamental state to n = 3. Number of spectral lines according to Bohr, is?

The kinetic energy of an electron revolving around a nucleus will be

(a) Four times of P.E.

(b) Double of P.E.

(c) Equal to P.E.

(d) Half of its P.E.

In a p-n junction with open ends:

1. There is no systematic motion of charge carriers.
2. Holes and conduction electrons systematically go from the p-side to the n-side and from the n side to the p-side respectively.
3. There is no net charge transfer between the two sides.
4. There is a constant electric field near the junction.

The electrical conductivity of pure germanium can be increased by:

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

What is the maximum energy that can be stored in a capacitor?

An isolated solid metallic sphere is given +Q charge. The charge will be distributed on the sphere

(a) Uniformly but only on surface

(b) Only on surface but non-uniformly

(c) Uniformly inside the volume

(d) Non-uniformly inside the volume

Rutherford’s a-particle experiment showed that the atoms have:

The impurity atoms with which pure silicon may be doped to make it a p-type semiconductor are those of:

1. Phosphorus.
2. Boron.
3. Antimony.
4. Aluminium.