D:-zero
Correct Answer:- Option-D
Question64:-When a particle of rest mass m attains the velocity of light, its mass becomes
A:-zero
B:-m
C:-infinity
D:-2m
Correct Answer:- Option-C
Question65:-For a conservative system, the slop of the potential energy versus position curve gives
A:-kinetic energy
B:-force
C:-power
D:-momentum
Correct Answer:- Option-B
Question66:-Are two simultaneous events, happening at the same point, simultaneous in all inertial frames ?
A:-yes
B:-no
C:-depends on the velocity of the frames
D:-none of these
Correct Answer:- Option-A
Question67:-The critical field of a superconductor at the critical temperature is
A:-inifinity

D:-depends on the superconductor
Correct Answer:- Option-B
Question68:-In a C60 fullerence molecule, how many pentagonal sides exist ?
A:-24
8:-6
:-20
D:-12
Correct Answer:- Option-D
Question69:-The open circuit voltage of a solar cell
A:-Increases with temperature first and then decreases
-decreases with temperature first and then increases
C:-Decreases with temperature
D:-Increases with temperature
Correct Answer:- Option-C

Question70:-The bandwidth of an amplifier is the range of frequencies at the limits of which its voltage gain falls by
from the maximum gain.

A:-1 dB
B:-3 dB
C:-9 dB
D:-70 dB
Correct Answer:- Option-B
Question71:-Which transistor configuration is commonly used for impedance matching ?
A:-common emitter
B:-common base
C:-common collector
D:-common mode
Correct Answer:- Option-C
Question72:-What is the hybridization in graphene ?
A:-sp
B:-sp2
C:-sp3
0-4
Correct Answer:- Option-B
Question73:-What happens to the X-ray diffraction peaks from a polycrystalline solid, when its crystalline size decreases ?
A:-become broad