A bullet of mass 10 g moving horizontally with a velocity of 400 m s - 1 strikes a wooden block of mass 2 kg which is suspended by a light inextensible string of length 5 m. As a result, the centre of gravity of the block is found to rise a vertical distance of 10 cm. The speed of the bullet after it emerges out horizontally from the block will be

Question

A bullet of mass 10 g moving horizontally with a velocity of 400 m s - 1 strikes a wooden block of mass 2 kg which is suspended by a light inextensible string of length 5 m. As a result, the centre of gravity of the block is 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

MARKS App · Accepted Answer

CM rises through height h, so its velocity after collision = 2 g h Apply conservation of linear momentum. 0.01 × 400 = 2 × 2 g h + 0.01 × v ⇒ v = 120 m/s

Search any question & find its solution

Looking for more such questions to practice?