Physics Objective Test No.14


    Multiple Choice Questions
1. The force on a particle with charge q and velocity in a magnetic field B is given by:
a) q (V x B )
b) -q (V x B )
c) q1(V x B )
d) q1( B xV )
Answer
2. The scalar quantities are described by their magnitude and _______
a) Direction
b) Proper unit
c) With graph
d) None of these
Answer
3.Average kinetic energy of molecules is
a) Directly proportional to square root of temperature
b) Directly proportional to absolute temperature
c) Independent of absolute temperature
d) Inversely proportional to absolute temperature
Answer
4.The specific heat of a gas in isothermal process is
a) Zero
b) Negative
c) Remains constant
d) Infinite
Answer
5.Latent heat of ice is 
a) Less than external latent heat of fusion
b) Equal to external latent heat of fusion
c) More then external latent heat of fusion
d) Twice the external latent heat of fusion
Answer
6.The r.m.s. velocity of the molecules in the sample of helium is 5/7th that of the molecules in the sample of hydrogen. If the temperature of the hydrogen sample is 0oC that of helium is 
a) 0oC
b) 0oK
c) 273oC
d) 100oC
Answer
7.Mean square velocity of five molecules of velocities 2 m/s, 3 m/s, 4 m/s, 5 m/s and 6 m/s is
a) 10 m2/s2
b) 18 m2/s2
c) 20 m2/s2
d) 15 m2/s2
Answer
8.The difference between the principal specific heats of nitrogen is 300 J/kg oK and ratio of the two specific heats is 1.4. then the CP is
a) 1050 J/kg oK
b) 650 J/kg oK
c) 750 J/kg oK
d) 150 J/kg oK
Answer
9.CP and CV denote the molar specific heats of a gas at constant pressure and at constant volume respectively. If Cp/Cv=γ and CP-CV=R, then CV is equal to
a) R/γ-1
b) γ-1/R
c) γR/γ-1
d)(R/γ-1)1/2
Answer
10.A gas is taken in a sealed container at 300 K. it is heated at constant volume to a temperature 600 K. the mean K.E. of its molecules is
a) Halved
b) Doubled
c) Tripled
d) Quadrupled