Question

A roller coaster starts at point y1=55m and only gets it to 37m at the second hill. The total distance is 520m and the wagon weights 1300 kg. How high is the average frictional force?

Answer 1

There has been a loss of energy that has turned into frictional work: If F is frictional force:
\[F \times d=F \times 520 =m \times g \times (55-37)=1300 \times 9.8 \times 18\]

Then: \[F=1300 \times 9.8 \times 18 / 520\]

Answer 2

Thank you !