A body of mass (4m) is lying in x-y plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass (m) move perpendicular to each other with equal speeds (v). The total kinetic energy generated due to explosion is :
A
mv2
B
$${3 \over 2}$$mv2
C
2mv2
D
4mv2
2
AIPMT 2014
MCQ (Single Correct Answer)
+4
-1
The force F acting on a particle of mass m is indicated by the force-time graph shown below. The change in momentum of the particle over the time interval from zero to 8 s is :
A
24 N s
B
20 N s
C
12 N s
D
6 N s
3
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
A person holding a rifle (mass of person and rifle together is 100 kg) stands on a smooth surface and fires 10 shots horizontally, in 5 s. Each bullet has a mass of 10 g with a muzzle velocity of 800 m s$$-$$1. The final velocity acquired by the person and the average force exerted on the person are :
A
$$-$$0.08 ms$$-$$1, 16 N
B
$$-$$0.8 ms$$-$$1, 8 N
C
$$-$$1.6 ms$$-$$1, 16 N
D
$$-$$1.6 ms$$-$$1, 8 N
4
NEET 2013
MCQ (Single Correct Answer)
+4
-1
An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass 1 kg moves with a speed of 12 m s$$-$$1 and the second part of mass 2 kg moves with 8 m s$$-$$1 speed. If the third part files off with 4 m s$$-$$1 speed, then its mass is :
