Problem 71GP

Problem

A car starts rolling down a 1 -in-4 hill (1 -in-4 means that for each 4 m traveled along the sloping road, the elevation change is 1 m). How fast is it going when it reaches the bottom after traveling 55 m? (a) Ignore friction. (h) Assume an effective coefficient of friction equal to 0.10.

Solution 71GP: We have to determine the velocity of the car as it is reaches the of the hill in presence and absence of friction. Step 1 of 8 Concept: Newton’s second law: The net force F acting on an object of mass m produces an acceleration a in that object. Mathematically, F= ma. Free body diagram of a body gives the diagrammatical representation of all the forces acting on the body in terms of magnitude and diagram, under the given situation. The kinematic equation relating the initial velocity (u)and final velocity (v) of an object, accelerating by an acceleration (a), having its displacement (s) is given as, v = u + 2as