A monoatomic gas is suddenly compressed to (1/8) of its initial volume adiabatically. The ratio of its final pressure to the initial pressure is : (Given the ratio of the specific heats of the given gas to be 5/3)
32
40/3
24/5
8
A Carnot engine takes heat from a reservoir at 627° C and rejects heat to a sink at 27°C. Its efficiency will be
3/5
1/3
2/3
200/209
A tuning fork A produces 4 beats/s with another tuning fork B of frequency 320 Hz. On filing one of the prongs of A,4 beats/s are again heard when sounded with the same fork B. Then, the frequency of the fork A before filing is
328 Hz
316 Hz
324 Hz
320 Hz
B.
316 Hz
There are 4 beats between A and B, therefore the possible frequencies of A are 316 or 324 that is (320 ± 4) Hz. When the prong of A is filed, its frequency becomes greater than the original frequency. If we assume that original frequency of A is 324 then on filing its frequency will be greater then 324. The beats between A and B will be more than 4. But it is given that the beats are again 4, therefore, 324 is not possible. Therefore,required frequency must be 316 Hz. (This is true, because on filing the frequency may increase so as to give 4 beats with B of frequency 320 Hz)
When the length of the vibrating segment of a sonometer wire is increased by 1%, the percentage change in its frequency is
1
2
The sprinkling of water reduces slightly the temperature of a closed room because
temperature ofwater is less than that of the room
specific heat of water is high
water has large latent heat of vaporisation
water is a bad conductor of heat
The equation of a simple harmonic wave is given by , where x and y are in metre and time is in second. The period of the wave in second will be
0.04
0.01
1
5
The loudness and pitch of a sound note depends on
intensity and frequency
frequency and number of harmonics
intensity and velocity
frequency and velocity
A rectangular vessel when full ofwater, takes 10 min to be emptied through an orifice in its bottom. How much time will it take to be emptied when half filled with water ?
9 min
7 min
5 min
3 min
If there were no gravity, which of the following will not be there for a fluid ?
Viscosity
Surface tension
Pressure
Archimedes' upward thrust
The term liquid crystal refers to a state that is intermediate between
crystalline solid and amorphous liquid
crystalline solid and vapour
amorphous liquid and its vapour
a crystal immersed in a liquid