Air conditioners use the same principles as refrigeration in order to cool indoor environments.

It is really hard for me right know

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?

Aball is thrown vertically upwards from the top of a tower with a speed of 100m/s. it strikes the pound near the base of the tower after 25sec . the height of the tower is