At 1 kilometer per year, how many centuries would it take for people to move from africa to china which is 10,000 kilometers away-

Shannon decides to check the accuracy of her speedometer. She adjusts her speed to read exactly 70 mph on her speedometer and holds this steady, measuring the time between successive mile markers separated by exactly 1.00 mile.

The engine of a locomotive exerts a constant force of 8.0 105 N to accelerate a train to 82 km/h. Determine the time (in min) taken for the train of mass 1.7 107 kg to reach this speed from rest. min

For this problem, imagine that you are on a ship that is oscillating up and down on a rough sea. Assume for simplicity that this is simple harmonic motion (in the vertical direction) with amplitude 5 cm and frequency 2 Hz.

If 48 cm of brick and 15 cm of fiberglass have the same R value, then ... both materials have the same density both materials have the same insulating ability both materials have the same conducting ability both materials have the same mass

If you were trying to build a sound proof room, which of the following materials would you choose in order to absorb the most sound, based on the coefficient of absorption for each material

What is the speed of sound in a vacuum?

An object has 60 j of potential energy and 40 j of kinetic energy. then 10 j of the potential energy is converted into kinetic energy. how much work was done on the object?

At what height above earth's surface is the gravitational acceleration reduced from its sea-level value by 0.40%?

A rocket moves away from the surface of the earth. As the distance r from the center of the planet increases, what happens to the force of gravity on the rocket?

Why am i not floating?