Physics – Multiple Choice Questions (MCQ) with Answers
1-A decrease in the Helmholtz function of a system is equal to:
(A) change in temperature
(B) external work done
(C) change in internal energy
(D) all the above
2-In a gas the transport of momentum gives rise to the phenomenon of:
(A) viscosity
(B) conduction
(C) diffusion
(D) volume
3-Joule-Thomson effect is related to:
(A) adiabatic compression
(B) adiabatic expansion
(C) isothermal expansion
(D) isothermal compression
4-The specific heat of a solid is 5 cal/g/ºC. Then heat required to raise its temperature by 20 ºC is:
(A) 150 cal
(B) 25 cal
(C) 100 cal
(D) 15 cal
5-P, T are ρ are the pressure, absolute temperature and density of an ideal gas, then:
(A) PT/ρ = constant
(B) Pρ/T = constant
(C) PT ρ= constant
(D) P/ρT = constant
6-For the system of diatomic gas the number of degrees of freedom are:
(A) 2
(B) 4
(C) 5
(D) 6
7-An LCR series ac circuit has the values of the resistance 400 Ω, capacitive reactance 400 Ω and inductive reactance 100 Ω then the total impedance of the circuit:
(A) 200 Ω
(B) 400 Ω
(C) 500 Ω
(D) 800 Ω
8-In an electromagnetic wave, the cross product of electric field E and magnetic field B gives:
(A) amplitude
(B) frequency
(C) velocity
(D) direction of travel
9-If dQ is the amount of heat supplied and dW is the work done, then in isothermal process:
(A) dQ + dW = 0
(B) dQ – dW = 0
(C) dW / dQ = 0
(D) None of the above
10-The physical quantity analogous to mass in circular motion is:
(A) moment of inertia
(B) force
(C) weight
(D) angular velocity
11-The value of g is 980 cm/s2. If the unit of length is taken as 1 km and unit of time as 1 minute, then the value of g becomes:
(A) 35.3 km/min2
(B) 36.2 km/min2
(C) 30.3 km/min2
(D) 980 km/min2
12-The escape velocity for a body on the earth is 11.2 km/s. If the radius of the earth is increased 4 times, then the escape velocity would be:
(A) 44.8 km/s
(B) 33.8 km/s
(C) 25.7 km/s
(D) 22.4 km/s
13-Compton effect is experimentally observed for:
(A) visible
(B) ultraviolet
(C) X-rays
(D) γ-rays
14-The e.m.f of a cell is quoted as 1.5V. This means that the cell can supply:
(A) 1.5A of current
(B) 1.5 coulombs of charge
(C) 1.5 Ωresistance
(D) 1.5 joules of energy per coulomb of charge
15-A ray of light is shone onto a prism. The light cannot be:
(A) deviated
(B) dispersed
(C) focused
(D) reflected
16-Cathode rays are:
(A) Beam of atoms moving towards cathode
(B) Beam of electrons emitted by cathode
(C) Is a beam of negatively charged ions moving towards anode
(D) Are electromagnetic waves
Answers:
1-B , 2-A , 3-B , 4-C , 5-D , 6-D , 7-C , 8-D , 9-A , 10-A , 11-A , 12-A , 13-C , 14-D, 15-D , 16-C