Question

A 225 kg crate is pushed horizontally by an applied force of 710 N over a surface with a coefficient of friction of 0.200. Draw the free-body diagram of the situation and calculate the acceleration of the crate.

Known:
m = 225 kg
Fapp = 710 N
u = 0.200
g = 9.8 m/s^2

Unknown:
a = ?

Equation:
Fnet = ma
Fapp - u * m * g = ma

What is the acceleration (a) of the crate in this situation?

A. 1.50 m/s^2
B. 2.40 m/s^2
C. 3.00 m/s^2
D. 4.20 m/s^2

Answer 1

The acceleration of the the crate in the situation is 3.00 m/s²

Force is the product of the mass of a body and the acceleration of the body.

force = mass × acceleration

For a body moving vertically, the body will move due to acceleration due to gravity.

therefore:

force = mass × acceleration due to gravity

The net force of a body when it undergoes frictional force is

F = force applied - frictional force.

frictional force = u × mg

= 0.2 × 225 × 9.8

= 441N

Net force = 710 - 49

= 661N

From

F = ma

a = F/m

a = 661/225

a = 3.00( to nearest whole number)

Therefore, the acceleration of the crate is

3.00 m/s²