The root mean square speed of oxygen molecule (O₂) at a certain temperature is v. If the temperature is doubled and the oxygen gas dissociates into atomic oxygen, the rms speed would be
Options […]
A cockroach is moving with a velocity v in anticlockwise direction on the rim of a radius R of mass m. The moment of inertia of the disc about the axis is I and it […]
A tuning fork frequency 512 Hz is vibrated with a sonometer wire and 6 beats per second are heard. The beat frequency reduces if the tension in the string is slightly increased. The original frequency […]
An artificial satellite is revolving round the earth in a circular orbit. Its velocity is half the escape velocity. Its height from earth’s surface is
Options
(a) 6400 km (b) 12800 km (c) […]
Two solid discs of radii r and 2r roll from the top of an inclined plane without slipping. Then
Options
(a) The bigger disc will reach the horizontal level first (b) The smaller […]
Three particles A,B and C are thrown from the top of a tower with the same speed. A is thrown straight up, B is thrown straight down and C is thrown horizontally. They hit the […]
If angular momentum of a body is increased by 200% its kinetic energy will increase by
Options
(a) 400% (b) 800% (c) 200% (d) 100%
Correct Answer:
800%
Explanation:
No explanation available. Be […]
The escape velocity of a body from earth’s surface is Ve. The escape velocity of the same body from a height equal to 7R from earth’s surface will be
Options
(a) Ve/√2 (b) […]
A small part of the rim of a fly wheel breaks off while it is rotating at a constant angular speed. Then its radius of gyration will
Options
(a) Increase (b) Decrease (c) Remain […]
Laser light is considered to be coherant because it consists of
Options
(a) many wavelengths (b) uncoordinated wavelength (c) coordinated waves of exactly the same wavelength (d) divergent beams
Correct Answer:
coordinated waves […]
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