Question

A 5-kg object is sliding to the right and encountering a friction force that slows it down. The coefficient of friction (μ) between the object and the surface is 0.1. What is the acceleration of the object? Note: There is no applied force here.

Answer 1

The friction force is 4.9 N

`a = 0.98\ m/s^2`

Step-by-step explanation:

Friction Force

When an object is moving and encounters friction in the air or rough surfaces, it loses acceleration or speed because the friction force opposes motion.

The friction force when an object moves on a horizontal surface is calculated by:

`Fr=\mu N`

Where
`\mu` is the coefficient of static or kinetics friction and N is the normal force.

If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:

N = W = m.g

Thus, the friction force is:

`Fr=\mu W`

The object has a mass of m=5 Kg, calculate the weight:

W = 5 * 9.8 = 49 N

It encounters a friction force that slows it down. We are given the coefficient of friction μ = 0.1, thus the friction force is:

Fr=0.1 49 N = 4.9 N

The friction force is 4.9 N

Since the only force acting on the object is the friction force, thus the net force is F = 4.9 N, and the acceleration can be calculated by using the equation of Newton's second law:

F = m.a

Solving for a:

`\displaystyle a = (F)/(m)`

`\displaystyle a = (4.9)/(5)`

`\mathbf{a = 0.98\ m/s^2}`