4.6 Exercise 1

A toboggan with two riders has a total mass of 85.0 kg. A third person is pushing with a force of 42.5 N in the direction of motion on a toboggan moving on a sloped surface at the top of a hill that has a downward angle of 15°. The force of friction on the toboggan is 31.0 N. Which statement describes an accurate free-body diagram to represent the situation?

1. An arrow of magnitude 10.5 N points down the slope of the hill.
2. An arrow of magnitude 833 N points straight down.
3. An arrow of magnitude 833 N points perpendicular to the slope of the hill.
4. An arrow of magnitude 73.5 N points down the slope of the hill.