A bead of mass 400 g is moving along a straight line under a force that delivers a constant power 1 . 2 W to the bead. If the bead is initially at rest, the speed it attains after 6 sec in m s - 1

Step-by-step solution

Work done = P t = 1 . 2 × 6 = 7 . 2   J From work-energy theorem we can write, ∆ K E = work done 1 2 × 0 . 4 × v 2 - 0 = 7 . 2 ⇒ v 2 = 36 ⇒ v = 6   m   s - 1