a horizontal force of 300.0N is required to push a 900.0 N crate across the floor at a constant speed. Find the coefficient of sliding friction.

the answer to this question is 60 n

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.