The spring extends by x on loading, then energy stored by the spring is (if T is the tension in spring and k is
spring constant
A cylinder contains 10kg of gas at pressure of 107 N/m2. The quantity of gas taken out of the cylinder, if final pressure is 2.5×106 N/m2 will be( temperature of gas is constant)
15.2 kg
3.7 kg
zero
7.5 kg
A resonance air column of length 40 cm resonates with tunning fork of frequency 450Hz. Ignoring end corrections , the velocity of sound in air will be
1020m/s
920m/s
820m/s
720m/s
If vibration of string is to be two times, then tension in the string must be made
Eight times
Four times
Twice
Half
A siren emitting sound of frequency 500 Hz is going away from a stationary listener with a speed of 50 m/s, the frequency of sound heard directly from the siren is
286.5 HZ
481 Hz
434.2 Hz
580 Hz
The kinetic energy of one molecule of a gas at normal temperature and pressure will be (k = 8.31 J/mole K)
1.7×103 J
10.2×103 J
3.4×103 J
6.8×103 J
A charged particle is suspended equillibrium in a uniform vertical electric field of intensity 2000V/m. If mass of the particle is 9.6×10-16 kg, the charge on it and excess number of electrons on the particle respectively are (g=10m/s2)
4.8×10-19 C,3
5.8×10-19 C,4
3.8×10-19C, 2
2.8×10-19 C, 1
A.
4.8×10-19 C,3
Charge of the particle is given by
A transmitting station transmits radiowaves of wavelength 360 m. Calculate the inductance of coil required with a condenser of capacity 1.20 μF in the resonant circuit to receive them
3.07×10-8 H
2.07×10-8 H
4.07×10-8 H
6.07×10-8 H
A circular coil of mean radius of 7 cm and having 4000 turns is rotated at the rate of 1800 revolutions per minute in the earth's magnetic field (B=0.5 gauss), the emf induced in coil will be
1.158 V
0.58 V
0.29 V
5.8 V
The peak value of alternating current is ampere. The mean square value of current will be
5 A
2.5 A
A
None of the above