Which of the following is not an example of perfectly inelastic collision ?
A bullet fired into a block if bullet gets embedded into block
Capture of electrons by an atom
A man jumping on to a moving boat
A ball bearing striking another ball bearing
A man slides down a light rope whose breaking strength is η times his weight .What should be his maximum acceleration so that the rope does not break ?
g (1 - η)
ηg
g /1+η
g/1 - η
A rocket with a lift of mass 20,000 kg is blasted upward with an initial acceleration of 5 m/s2 .Calculate the initial thrust of the blast.
3.25 x 105 N
2.96 x 105 N
4.35 x 105 N
1.45 x 105 N
A body of mass 0.1 kg attains a velocity of 10 m/s in 0.1s.The force acting on them is:
10 N
0.001 N
0.01 N
1000 N
A lift is moving upward with increasing speed with acceleration 'a'.The apparent weight will be :
less than the actual weight
more than the actual weight and have a fixed value
more than the actual weight which increases as long as velocity increases
zero
A certain force applied to a mass m1 gives it an acceleration of 15 m/s2 .The same force applied to a mass m2 gives it an accelerationof 10 m/sec2 .If the two masses are fixed together and the same force is applied to the combination ,find the acceleration.
6 ms-2
0.6 ms-2
4 ms-2
none of these
A body of mass 10 kg falls vertically on a muddy ground with a velocity of 20 m/s and penetrates through a vertical depth of 0.3 m.Calculate the average force exerted by the muddy ground.Take g = 10 m/s2 .
6767 N
7894 N
7845 N
5894 N
A light string passing over a smooth light pulley , connects two blocks of masses m1 and m2 (vertically).If the acceleration of the system is (g/8),then the ratio of masses is
8 : 1
9 : 7
4 : 3
5 : 3
Two forces of 6N and 8N act on a body of mass 7kg. The maximum value of acceleration produced cannot be more than
2ms-1
4ms-1
6ms-1
8ms-1
A gun of mass 1kg fires a bullet of mass 1g with a velcoity of 1ms-1.The recoil velcotiy of the gun is
1ms-1
0.1ms-1
0.01ms-1
0.001ms-1
