Standard +0.3 This is a straightforward mechanics problem requiring application of impulse-momentum theorem, coefficient of restitution, and friction work-energy principles in a standard sequence. While it involves multiple steps (finding rebound speed using work-energy, then calculating impulse), each step uses routine M1 techniques with no novel insight required, making it slightly easier than average.
3. A particle \(P\) of mass 0.4 kg is moving on rough horizontal ground when it hits a fixed vertical plane wall. Immediately before hitting the wall, \(P\) is moving with speed \(4 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) in a direction perpendicular to the wall. The particle rebounds from the wall and comes to rest at a distance of 5 m from the wall. The coefficient of friction between \(P\) and the ground is \(\frac { 1 } { 8 }\).
Find the magnitude of the impulse exerted on \(P\) by the wall.
3. A particle $P$ of mass 0.4 kg is moving on rough horizontal ground when it hits a fixed vertical plane wall. Immediately before hitting the wall, $P$ is moving with speed $4 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ in a direction perpendicular to the wall. The particle rebounds from the wall and comes to rest at a distance of 5 m from the wall. The coefficient of friction between $P$ and the ground is $\frac { 1 } { 8 }$.
Find the magnitude of the impulse exerted on $P$ by the wall.\\
\hfill \mbox{\textit{Edexcel M1 2016 Q3 [7]}}