Moderate -0.8 This is a straightforward application of the work-energy principle with a single force and simple arithmetic. Students need only recall that work done equals change in kinetic energy, then substitute values into ½mv² and solve for R. No problem-solving insight or multi-step reasoning required beyond the direct formula application.
A particle of mass 4 kg is moving in a straight horizontal line. There is a constant resistive force of magnitude \(R\) newtons. The speed of the particle is reduced from 25 m s\(^{-1}\) to rest over a distance of 200 m.
Use the work-energy principle to calculate the value of \(R\).
[4]
A particle of mass 4 kg is moving in a straight horizontal line. There is a constant resistive force of magnitude $R$ newtons. The speed of the particle is reduced from 25 m s$^{-1}$ to rest over a distance of 200 m.
Use the work-energy principle to calculate the value of $R$.
[4]
\hfill \mbox{\textit{Edexcel M2 Q1 [4]}}