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featherua08
Mar27-08, 09:44 PM
1. The problem statement, all variables and given/known data
How much work is required to push a 25-kg block up 2m up a frictionless 30 degree incline at a constant speed?


2. Relevant equations
W=F(delta X) ; W=(F cos theta)(delta X)


3. The attempt at a solution
I did n=mg -- n=(25)(9.8)=245 & that is the correct answer..but I don't understand how.

Snazzy
Mar27-08, 09:53 PM
Well, by coincidence you didn't factor in the angle and still go the right answer.

Start off by having a coordinate plane that is parallel to the incline of the ramp. Figure out what component of the total weight (mg) you are pushing up the ramp and by what distance.

featherua08
Mar27-08, 09:57 PM
I don't think I understand what you mean. The distance is 2m and wouldn't the total weight simply be the weight of the block?