162614 A car of weight \(\mathbf{W}\) is on an inclined road that rises by \(100 \mathrm{~m}\) over a distance of \(1 \mathrm{~km}\) and aplied a constant frictional force \(W / 20\) on the car. While moving uphill on the road at a speed \(10 \mathrm{~ms}^{-1}\), the car needs power \(P\). If it needs power \(P / 2\) while moving downhill at speed \(v\) then value of \(v\) is :
162614 A car of weight \(\mathbf{W}\) is on an inclined road that rises by \(100 \mathrm{~m}\) over a distance of \(1 \mathrm{~km}\) and aplied a constant frictional force \(W / 20\) on the car. While moving uphill on the road at a speed \(10 \mathrm{~ms}^{-1}\), the car needs power \(P\). If it needs power \(P / 2\) while moving downhill at speed \(v\) then value of \(v\) is :