Mechanics | Relativity Answers

When do action and reaction forces within a system not cancel each other?

What is the net force acting on a 12-N falling object when it encounters 5-N of air resistance?

What is the net force that acts on an object that weighs 10 newtons if the object is in freefall?
Why is it that a light object accelerates at the same speed as a heavier object in free fall?

A rectangular crate weighing 40kg is too hard for Johnny to push due to friction. If instead of laying flat the crate was standing up on end would it be easier for Johnny to push?

If Frankie the kangaroo climbed out of the crate and pushed the crate with a mighty 12 newtons of force against the efforts of Fred and the man (each applying 10 newtons of force), what would be the net force on the crate from all the pushing?

If a goat pushes on a crate with 10 newtons of force and a man pushes back on the crate from the opposite direction with also 10 newtons of force, what is the net force of the goat and the man on the crate?

If rotational speed of a disc remains constant, what happens to the speed of a point on the disc if its distance from the axis is doubled?

If the rotational speed of a disc is doubled, what happens to the tangential speed of any point on the disc?

The distance moved per unit of time is?

A car drives off a vertical cliff that is 122.5m tall. If the car lands 100m from the base of the cliff what was the cars speed as it drove off the cliff.