What is the acceleration of the mass?

Question

A 54 newton horizontal force pushes a 5.0 kg mass sitting on the horizontal surface. Additionally, the horizontal surface exerts a 30 newton frictional force on the mass. What is the acceleration of the mass?

Answer 1

The sum of the forces is 54 - 30 = 24 N

F = ma so a = F/m

Plugging in the numbers we get a = 24/5 = 4.8 m/s²