Answer:
2.28 m/s²
Explanation:
Draw a free body diagram of the box. There are four forces on the box:
Weight force mg pulling down.
Normal force Fn pushing up.
Applied force F pushing right.
Friction force Fn μ pushing left.
Sum the forces in the y direction.
∑F = ma
Fn − mg = 0
Fn = mg
Sum the forces in the x direction.
∑F = ma
F − Fn μ = ma
F − mg μ = ma
a = (F − mg μ) / m
a = (650 N − 150 kg × 9.8 m/s² × 0.21) / 150 kg
a = 2.28 m/s²
