A rocket consumes fuel at the rate of 100 kg/s and
the exhaust gases are ejected at a speed of 45 km/s.
The rocket would then experience a thrust (in MN)
equal to
2.25
4.5
0.45
0.225
A body has linear momentum P and translational kinetic energy E. If momentum becomes 2P, the kinetic energy will have the value
0.5 E
E
2E
4 E
The kinetic energy of a body is stated to increase by 300 percent. The corresponding increase in momentum of the body will be
50
100
200
300 percent
Two particles with masses in the ratio 1:4 are moving with equal kinetic energies. The magnitude of their linear momentums will confirm to the ratio
1 : 8
1 : 2
4 : 1
Two similar balls are allowed to fall from different heights h1 and h 2. The ratio of their linear moment at half of their heights will be
A man weighing 60 N jumps off a railway train running
on horizontal rails at 20 km/hr with a packet weighing 100 N 10 his hand. The thrust of packet on his hand is
Zero
100 N
500 N
700 N
Two balls of mass 2 kg and 4 kg respectively are connected to the two ends of a spring. The balls are pressed together and placed on a smooth table. When released, the lighter ball moves with an acceleration of 2 m/s2. The acceleration of the heavier ball will be
0.5 m/s2
1 m/s2
2 m/s2
4 m/s2
A 150 gm cricket ball moving at 20 m/s is caught by a player and the catching process is completed in 0.1 second. The force of blow exerted by the ball on the hands of player is
3 N
8 N
24 N
30 N
A ball weighing 0.01 kg hits a hard surface vertically with a speed of 5 m/s and rebounds with the same speed. The ball remains in contact with the surface for 0.01 second. The average force exerted by the surface on the ball in Newton’s is
0.1
1.0
5.0
10.0
/
1.5 m/s
3.0 m/s
4.7 m/s
6.3 m/s