Answer to Question #328978 in Mechanics | Relativity for Tracey

Question

A toboggan carrying two children (total mass = 85 kg) reaches its maximum speed at the bottom of a hill, and then glides to a stop in 21 m along a horizontal surface.The coefficient of kinetic friction between the toboggan and the snowy surface is 0.11.

(a) Draw a FBD of the toboggan as it slows down, and calculate the magnitude of ALL the forces in the diagram.

(b) Calculate the acceleration of the toboggan.

(c) Calculate the work done on the toboggan by the friction on the snowy surface.Should the work be positive or negative?Explain.

Answer 1

$a=\mu g=1.1~\frac m{s^2},$

$A=-F_{fr}l=-\mu mgl=-mal=-2~kJ.$