Solving "An Person Pushes a Box Up a Hill: A Physics Problem

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The physics problem involves calculating the acceleration of a box being pushed up a 30-degree incline with a force of 450N, a mass of 20kg, and a friction force of 20N. The original calculation yielded an acceleration of 16.6 m/s², but the expected answer was 1.9 m/s². After resolving the forces into components, it was confirmed that the calculated acceleration should indeed be around 16.6 m/s², indicating a misunderstanding of the problem's parameters. The discussion highlights the importance of correctly applying the principles of force resolution and friction in physics problems. The final consensus is that the initial calculation was accurate, and the box's acceleration is significantly higher than 1.9 m/s².
danago
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Hey. I've been given this problem:

"An person wishes to push a box up a hill, inclined at 30 degrees. He is able to push with a force of 450N. If the box has a mass of 20kg, and a force of friction with magnitude 20N applies, what is the acceleration of the box?"

I drew a diagram, and came up with this:
http://img135.imageshack.us/img135/1124/incplaneob0.gif

What i did was resolve all of the forces into their components (parallel and perpendicular to the slope), including the weight and normal force, and then add them all.

I got an answer of 16.6 ms^-2, but apparently the answer is 1.9 ms^-2. Would someone be able to maybe quickly work it out, and tell me what the real answer is?

Thanks very much,
Dan.
 
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(450-20-20*9.81*sin(30))/20 = 16.595, so you should be correct. The box should have an acceleration plenty over 1.9 m/s2 even if the hill was vertical.
 
ok thanks for confirming that :-)
 

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