7. A girl pushes her little brother on his sled with a force of 300. N for 750. m. How much work is this if the force of friction acting on the sled is (a) 200. N. (b) 300. N?

Atelevision set that has been running for a while heats up even the air around it. which two laws of thermodynamics could be used to analyze this scenario

Blank is the perceived frequency of a sound wave

Aball is rolled uphill a distance of 5 m before it slows, stops, and begins to roll back. the ball rolls downhill 9 m before coming to rest against a tree. what is the magnitude of the balls displacement? a. 4 meters b. 9 meters c. 14 meters d. 45 meters