Physics Test 177

A diatomic gas initially at 18C is compressed adiabatically to one eighth of its original volume. The temperature after compression will be

N molecules, each of mass m, of gas A and 2 N molecules, each of mass 2 m, of gas B are contained in the same vessel which is maintained at a temperature T. The mean square velocity of molecules of B type is denoted by V₂ and the mean square velocity of A type is denoted by 

The bob of a simple pendulum executes simple harmonic motion in water with a period t, while the period of oscillation of the bob is t0 in air. Neglecting frictional force of water and given that the density of the bob is (4/3) × 1000 kg/m₃. The relationship between t and t₀ is

The frequency of whistle of an engine appears to be (4/5)th of initial frequency when it crosses a stationary observer. If the velocity of sound is 330 m/s, then the speed of engine will be

Two point dipoles of dipole moment The force between the dipoles is :

Which of the following figure shows the correct equipotential surfaces of a system of two positive charges?

The e.m.f. developed in a thermo-couple is given by

where T is the temperature of hot junction, cold junction being at 0C. The thermo electric power of the couple is

A battery is connected between two points A and B on the circumference of a uniform conducting ring of radius r and resistance R. One of the arcs AB of the ring subtends an angle θ at the centre. The value of the magnetic induction at the centre due to the current in the ring is

A watch glass containing some powdered substance is placed between the pole pieces of a magnet. Deep concavity is observed at the centre. The substance in the watch glass is

As a result of change in the magnetic flux linked to the closed loop shown in the fig, an e.m.f. V volt is induced in the loop. The work done (joule) in taking a charge Q coulomb once along the loop is