A bullet of mass 10 g moving horizontal with a velocity of 400 m s-1 strikes a wood block of mass 2 kg which is suspended by light inextensible string of length 5 m. As result, the centre of gravity of the block found to rise a vertical distance of 10 cm. The speed of the bullet after it emerges out horizontally from the block will be
100 m s-1
80 m s-1
120 m s-1
160 m s-1
As we learnt in
Impulse Momentum Theorem -
- wherein
If is increased, average force is decreased
Apply conservation of momentum
Option 1)
100 m s-1
Incorrect
Option 2)
80 m s-1
Incorrect
Option 3)
120 m s-1
Correct
Option 4)
160 m s-1
Incorrect