Based on the Newton second law, you can write the following equation:
[tex]F-F_r=ma[/tex]
where,
F: applied force = 690.0N
Fr: friction force = μN
μ: coefficient of friction = 0.31
N: normal force = m*g
m: mass of the desk = 130.0kg
g: gravitational acceleration constant = 9.8m/s^2
Solve the equation above for a, replace the previous values of the parameters and simplify, as follow:
Hence, the acceleration of the crate is 295.06m/s^2
