Question

In a roller coaster, where is friction the greatest, or at its peak?

Yes, I understand there is friction throughout the ride, but I need clarifications if the friction is at its greatest at the end of the ride or the loop-the-loop part.

Answer 1

When `F_n` is greatest (more in contact with surface) or when the roller coaster is more massive.

Explanation:

If the force of friction is defined as the coefficient of friction times the normal force, then it when the roller coaster is in contact with the rails more.
`F_f = muF_n`
`F_n = F_g`
where `F_g` equals `mg`
And `mu` is constant
then the only variable affecting it is the normal force or the mass.