Select all that apply. No work is accomplished in which of the following situations? 1.A refrigerator on rollers is pushed across a level floor at a constant velocity. 2.A girl pulls up on a window to open it, but it won't move. 3.A boy lifts a 4.0-newton box to a height of 1.0 meters.

What property is a characteristic of a substance that can be observed and does not change the identity of the substance

Agroup of students were investigating the force of gravity. they began by dropping a foam ball from a height of 3 meters into a bucket of sand. the ball hit the sand in 0.306 seconds. they dropped additional balls of approximately the same diameter, but of different masses. here is the data they collected. based on this experiment and the collected data, what would their conclusion be?

Give an example of a collision in real life. use the law of conservation of energy to describe the transfer of momentum. be sure and discuss the momentum before and after the collision occurs. you will need at least 3 sentences to thoroughly answer this question.