Mathematics 9709 · AS & A Level · Energy, work and power
Energy, work and power — practice question
Particle $P$, with mass $0.4\,\text{kg}$, is fired straight up from level ground at a speed of $10\,\text{m s}^{-1}$.
(a)[2]
Calculate the maximum height above the ground attained by $P$.
(b)[4]
After $P$ returns to the ground, it rebounds vertically upward. At the first moment it strikes the ground, $P$ loses $7.2\,\text{J}$ of energy. Find the time interval between the first and second times that $P$ hits the ground.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “A valid method is shown, such as $v^2=u^2+2as$ with $v=0$, or an energy equation like $0.4gh=\tfrac12(0.4)(10)^2$.” …