How much force is needed to push a shopping cart up an incline?

[owenhigdon]

A shopper pushes a 7.5kg shopping cart up a 13 degree incline.



I need to find the force required to give the cart an acceleration of 1.41m\s\s up the incline.



ive tried breaking the weight, force and acceleration into components but i just end up getting more confused...any help on this would be great, thanks for your time.

 

[cimon9999]

F=ma

If it was on level ground and you wanted it to go at 1.4ms-2, the force needed would be just 7.5*1.4=10.5N

Now because it's on an incline you have to add in that component also. This diagram should explain it:

http://instruct.tri-c.edu/fgram/web/Image86.gif

You need to counteract the mgsin0 by supplying that force in the opposite direction - up the slope.

So that is 7.5*9.8*Sin13 = 16.53N

Add the two together and you get 27.03N

Eamon

 

[owenhigdon]

Wow, now i understand! thanks so much for your help!