Question 7(Multiple Choice Worth 2 points) In the table below, which statement would best fill the missing box under "Open System"?
Open System
Closed System
Matter freely moves
Matter does not freely move
Energy can enter or leave
O Energy is constant
O Energy is not exchanged
Energy is freely exchanged
O Energy does not freely move

A500g object falls off a cliff and losers 100 j from its gravitational potential energy store. if the gravitational field strength g=9.8n/kg, how high is the cliff?

Aball has an initial velocity of 3 m/s. if there is no friction, what is the highest it could roll?

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?