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# A cyclist comes to a skidding stop in 10 m. During this process, the force on the cycle due to the road is 200 N and is directly opposed to the motion.How much work does the road do on the cycle?

$\begin{array}{1 1}-2000J\\-1000J\\-3000J\\1500J\end{array}$

Work done on the cycle by the road is the work done by the stopping (frictional) force on the cycle due to the road
The stopping force and the displacement make an angle of $180^{\large\circ}$ ($\pi$ rad) with each other.
Thus, work done by the road,
$W_r=Fd\cos\theta$
$\;\;\;\;\;\;= 200\times 10\times \cos \pi$
$\;\;\;\;\;\;= -2000J$