Question

Nicola ans Sofia are ski racing on a 15 degree slope. The race consist of going in a straightfine until the end of the slope. Their respective masses are 75 Kg and 53 Kg. Considering there is a coefficient of kinetic ifction of 0.12, which of these affirmation is true? Select one: In theory, they should arrive at the same time as the bottom of the hill. Nicolas will arrive first at the bottom of the hill since his mass is bigger Sofia will arrive first at the bottom of the hill since her force of friction is smaller Sofia will arrive last at the bottom of the hill since her force of friction is bigger

Answer 1

Net force along the direction of motion

$F_{net}= mgsin\theta- \mu mgcos\theta$

$F_{net}= ma= mgsin\theta-\mu mgcos\theta$

Acceleration a

$a= g(sin\theta-\mu cos\theta)$

Acceleration is independent of the mass of sliding person.

Answer is.

In theory, they should arrive at the same time at the bottom of the hill.