A block of the mass of 1 kg is moving on the x -axis. A force F acting on the block is shown. The velocity of the block at time t = 2 s is - 3 m s - 1 . What is the speed of the block at time t = 4 s ?

Question

A block of the mass of 1 kg is moving on the x -axis. A force F acting on the block is shown. The velocity of the block at time t = 2 s is - 3 m s - 1 . What is the speed of the block at time t = 4 s ?, 8 m s - 1, 2 m s - 1, 3 m s - 1, 5 m s - 1

MARKS App · Accepted Answer

Given, the mass of block m = 1 k g The velocity of the block at time t = 2 s is - 3 m s - 1 Impulse during t = 2 s to t = 4 s . From the graph, I = A r e a o f ΔABC + A r e a o f ΔCDE = 1 2 3 - 2 × 5 + 1 2 ( 4 - 3 ) ( - 5 ) = 5 2 - 5 2 = 0 We know that, Impulse = Change in momentum 0 = m v f - m v i ⇒ m v f - m v i = 0 ⇒ m v f = m v i v f = v i = - 3 m s - 1 or | 3 m s - 1 |

Search any question & find its solution

Looking for more such questions to practice?