(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

You use 556 N of constant force to push a crate 12 m horizontally across the floor, and then stop pushing, leaving the crate stopped in its new position:

a) How much work did you do on the crate?

b) What is the change in the total mechanical energy of the crate after being pushed (ingoring heat)?

2. Relevant equations

F(cos theta)d

3. The attempt at a solution

ANSWERS (from teacher):

a) 6672 J

b) 0 J

i know how to find the first question. you use the equation i gave. F is 556 N, cos theta is 1, and d is 12 m.

i dont understand how the second part is 0. am i supposed to use a certain formula? i know PE and KE but i dont have a mass in the problem. so what am i supposed to use to figure out what mechanical energy is?

if you could help me it would be great

i have a test on next tuesday

tryna study now instead of later

thank you!:tongue2:

sweedeljoseph

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# Homework Help: Mechanical energy?

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