Define the term acceleration.
A man rides a toboggan down a snow-covered slope from point A to point B and then on to point C. The route is shown in Fig. 1.1. The slope AB makes an angle of $40^{\circ}$ with the horizontal, and the slope BC makes an angle of $20^{\circ}$ with the horizontal. Friction is not negligible. The man and toboggan together have a combined mass of $95\ \text{kg}$. He leaves A from rest and moves with constant acceleration between A and B. It takes him $19\ \text{s}$ to reach B, where his speed is $36\ \text{m s}^{-1}$.
Calculate the acceleration over the journey from A to B.
Show that the distance covered from A to B is $340\ \text{m}$.
For the man and toboggan travelling from A to B, calculate the change in kinetic energy.
For the man and toboggan travelling from A to B, calculate the change in potential energy.
Use your answers in (iii) to determine the average frictional force acting on the toboggan between A and B.
A parachute opens on the toboggan as it passes point B. From B to C, there is a constant deceleration of $3.0\,\text{m s}^{-2}$. Calculate the frictional force that causes this deceleration between B and C.