Physics

A man, using a 70 kg garden roller on a level surface, exerts a force on 200N at 30 degrees to the ground. Find the vertical force of the roller on the ground if he pulls; and if he pushes the roller.
Assume g = 10m/s^2
If he pulls, vertical force on the ground
= 70x10 - 200sin30
= 700 - 200x1/2
= 600N
If he pushes, vertical force on the ground
= 70x10 + 200sin30
= 700 + 200x1/2
= 800N
A man tries to push a cargo along horizontal ground, but he finds that he cannot move it. If the force he exerted on the cargo is 800N, show the direction of the frictional force on the cargo and give its value.
The frictional force will be 800N in the hoirzontal direction against the force applied by the man.