Question

During vertical motion under gravity a body passes through a point at 4sec and 12sec in upwards and downwards journeys. The speed at this point is

Answer 1

Answer:

40 m/s

Explanation:

During vertical motion under gravity a body passes through a point at 4sec and 12sec in upwards and downwards journeys. The speed at this point is

Let say Initial Velocity = V

Velocity after 4 sec = V - 4g

Velocity after 12 secs = V - 12g

One velocity is upward & other is downward &

=> V - 4g + V - 12g = 0

=> 2V = 16g

=> V = 8g

=> V = 80 m/s   ( g = 10 m/s²)

Velocity at that point = 80 - 40 = 40 m/s  or - 40 m/s