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

A crate with a weight of [itex]50N[/itex] rests on a horizontal surface. A person pulls horizontally on it with a force of [itex]10N[/itex] and it does not move. To start it moving a second person pulls vertically upwards on the crate. If the coefficient of static friction is [itex]0.4[/itex], what is the smallest vertical force which will move the crate.

2. Relevant equations

[itex]f_s=\mu_sn[/itex]

3. The attempt at a solution

[itex]R(\rightarrow): 10 - f_s = 0 \implies f_s = 10N[/itex]

[itex]f_s=\mu_sn_{tot} = (0.4)(n_{tot}) = 10 \implies n_{tot} = 25[/itex]

[itex]n_{tot} = F_y+n \implies F_y = 25-50 =-25N[/itex]

4. The problem I encounter

Can you check my method please. I got [itex]-25N[/itex] which is negative hence this is giving me a doubt. Thanks.

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# Homework Help: What is the smallest vertical force which will move the crate

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