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

NO CALCULATOR ALLOWED.

a 50-kilogram box is pushed up a 1.5m-meter incline with an effort of 200 newtons. The top of the incline is 0.5 meter above the ground. How much work was done to overcome friction?

(A) 55J

(B) 75J

(C) 245J

(D) 300J

(E) 490J

The inclination in the question above is an example of a simple machine. On the basis of the information provided, what is the approximate efficiency of this machine?

(A) 50%

(B) 100%

(C) 20%

(D) 10%

(E) 80%

2. Relevant equations

[tex]W = Fd [/tex]

[tex]F_{fric} = \mu F_{n} [/tex]

[tex]W = E [/tex]

[tex] e = \frac{\Delta W}{W_{tot}} [/tex]

3. The attempt at a solution

Alright so the total work has to be 200*1.5; thus, [tex] W_{TOT} = 200*1.5 = W_{fric} + W_{frictionless} [/tex]

Or

[tex]W_{nc} = W_{TOT} - W_{frictionless} [/tex]

and idk what to do from here ;\

the efficiency part:

e =

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# Homework Help: How much work was done to overcome friction?

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