Apoliceman's whistle has a high pitch low amplitude low pitch

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

10 points! will mark brainiest! in a heat engine if 1,000 j of heat enters the system and the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2,000 j 1: write the equation 2: list out your known variables 3: plug the numbers into the equations 4: solve 5: write your solution statement that includes initial energy and final energy added you so much!

Ascientist wants to test ways to reduce pollution in lake . what is the bestway of doing this