An airplane starts at rest and accelerates down the runway for 20 s. at the end of the runway, its velocity is 80 m/s north. what is its acceleration?

A6,600 kg train car moving at +2.0 m/s bumps into and locks together with one of mass 5,400kg moving at -3.0m/s. what is their final velocity? +0.50 m/s -1.0 m/s +2.5 m/s -0.25 m/s

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

At very high pressures, gases become and will eventually a) more dense; become hotter b) more dense; change to a liquid or solid c) less dense; combust d) less dense; turn into a liquid