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# Which answer is correct??? :confused: watch

1. A 3kg mass is on a smooth slope inclined at 30 degrees to the horizontal. What horizontal force needs to be applied to keep the body in place? I get 16.97 N but my friend gets 12.73. Please help!
2. I get 16.97
3. (Original post by 2710)
I get 16.97
Cool thanks! Anyone else?
4. Wouldn't it be better to ask to show your friends working?
5. (Original post by 2710)
Yeah... we have tried to discuss it.
6. (Original post by innerhollow)
Well, let's see. A 3kg mass has weight of 3*9.8, which is 29.4N

This would mean that to stop it, you'd need a force equal to the component of the weight acting down the slope, which would be 29.4*sin30, which is 14.7N

... What the hell?! Um, how did both of you get 16.97N?
You are applying a horizontal force. Not a force perpendicular to the slope

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