Mathematics 9709 · AS & A Level · Energy, work and power
Energy, work and power — practice question
A straight slope with length $60\,\text{m}$ is inclined at an angle of $12^\circ$ to the horizontal. A bobsled begins at the top of the slope with a speed of $5\,\text{m s}^{-1}$. It travels directly down the slope.
(a)[3]
It is stated that the bobsled experiences no resistance. Determine its speed when it gets to the bottom of the slope.
(b)[5]
Now the coefficient of friction between the bobsled and the slope is given as $0.03$. Determine how long it takes the bobsled to reach the bottom of the slope.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Acceleration correctly obtained from $mg\sin12=ma$, so $a=2.08$” …