The correct option is C 15 kg cycle moving with a speed of 0.8 ms−1
Momentum is given by:
p=mv
Case I:
Mass of ball, mb=600 g=0.6 kg
Velocity of ball, vb=18 m s−1
Momentum of ball, pb=0.6×18=10.8 kg m s−1
Case II:
Mass of cycle, mc=15 kg
Velocity of cycle, vc=0.8 m s−1
Momentum of cycle, pc=15×0.8=12 kg m s−1
Case III: As the velocity of rock is zero, its momentum will be zero.
Case IV:
Mass of the body = 5 kg
Velocity of the body = 1.5 m s−1
Momentum = 5×1.5=7.5 kg m s−1
Therefore out of the given cases, the cycle will have the greatest momentum.