- AFor an electron as well as for a photon.
- BFor an electron but not for a photon.
- CFor a photon but not for an electron.
- DNeither for an electron nor for a photon.
Explanation:
The equation E = pc is valid for a particle with zero rest mass. The rest mass of a photon is zero, but the rest mass of an electron is not zero. So, the equation will be valid for photon, and not electron.
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The dielectric strength of air at NTP is 3
then the maximum charge that can be given to a spherical conductor of radius 3 m is
|
(a) 3 |
(b) 3 |
(c) 3 |
(d) 3 |
A wire has a resistance of 12 ohm. It is bent in the form of equilateral triangle. The effective resistance between any two corners of the triangle is
|
(a) 9 ohms |
(b) 12 ohms |
(c) 6 ohms |
(d) 8/3 ohms |
A dip circle is at right angle to the magnetic meridian. What will be the apparent dip
| (a) 0° | (b) 30° | (c) 60° | (d) 90° |
During a negative beta decay
|
(a) An atomic electron is ejected |
|
(b) An electron which is already present within the nucleus is ejected |
|
(c) A neutron in the nucleus decays emitting an electron |
|
(d) A part of the binding energy is converted into electron |
An ammeter reads upto 1 ampere. Its internal resistance is 0.81 ohm. To increase the range to 10 A the value of the required shunt is
|
(a) 0.09 W |
(b) 0.03 W |
(c) 0.3 W |
(d) 0.9 W |
The formula for induced e.m.f. in a coil due to change in magnetic flux through the coil is (here A = area of the coil, B = magnetic field)
|
(a) e = - A. |
(b) e = -B. |
(c) e = - |
(d) e = - |
If Fresnel’s biprism experiment as held in water inspite of air, then what will be the effect on fringe width
|
(a) Decrease |
(b) Increase |
(c) No effect |
(d) None of these |