A kg object has 400 j of potential energy. Find how high off the groumd the object is

A 30 ton rail car and a 90 ton rail car, initially at rest, are connected together with a giant but massless compressed springbetween them. When released, the 30 ton car is pushed away at aspeed of 4.0 m/s relative to the 90 ton car.

A 30 gram bullet is shot upward at a wooden block. The bullet is launched at the speed vi. It travels up 0.40 m to strike the wooden block. The wooden block is 20 cm wide and 10 cm high and its thickness gives it a mass of 500 g.

About 30 miles Into Earth, the speed of selsmic (earthquake) wave ut 30 miles Into Earth, the spe of seismic (eartha e) waves Increases.

If you apply 100.0 N of force to lift an object with a single, fixed pulley, then what is the resistive force?

Two bumper cars colide into each other and each one bounces bach. wich of Newton's laws is it?

Let y'=4 x. find all values of r such that y = rx^{2} satisfies the differential equation. if there is more than one correct answer, enter your answers as a comma separated list.

What are the starting materials for nuclear fission

Why is it possible to throw a 0.145 kg baseball much further than a 7 kg bowling ball?

What is the name of the force that opposes or slows down the motion of objects

If you jump into the air, are your legs pushing you away from the earth or pushing the earth away from you?