A helter-skelter ride has a spiral slide. The top of the slide is \(7\text{ m}\) higher than the bottom. The average frictional resistance is \(50\text{ N}\). A boy of mass \(60\text{ kg}\) slides down, starting from rest. At the bottom he has speed \(10\text{ m s}^{-1}\).

Find the length of the slide.

Enter just the number.

A helter-skelter ride has a vertical drop of \(7\text{ m}\). A boy of mass \(60\text{ kg}\) starts from rest and reaches the bottom with speed \(10\text{ m s}^{-1}\).

Work out the amount of mechanical energy lost.

Enter just the number in joules.

A boy slides down a helter-skelter and some mechanical energy is lost because of friction.

What form of energy has most of this lost mechanical energy been changed into?

A box of mass \(10\text{ kg}\) slides \(3\text{ m}\) down a rough slope inclined at \(30^\circ\) to the horizontal. At the top of the slope its speed is \(3.25\text{ m s}^{-1}\) and at the bottom its speed is \(5\text{ m s}^{-1}\).

Find the coefficient of friction between the box and the slope.

Enter just the number.

A sack of mass \(12\text{ kg}\) slides down a ramp, starting from rest at a height of \(2\text{ m}\) above the ground. It reaches the ground with speed \(6\text{ m s}^{-1}\).

Work out the amount of mechanical energy dissipated.

Enter just the number in joules.