Calculating Forces & Friction on a Block Resting on an Incline

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To determine the horizontal force required to push a 5 kg block on a 30-degree incline with a static friction coefficient of 0.2, the equation ma = Fapp - (m)mg - mgsin30 is used. The discussion emphasizes the need to clarify whether the force is for moving the block up or down the incline and the direction of friction. Participants suggest avoiding immediate substitution of numbers to focus on the conceptual understanding of forces involved. The conversation also touches on the implications of the block's acceleration in both scenarios. Understanding these dynamics is crucial for calculating the necessary force to initiate movement.
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A 5 kg block rests on a 30degree incline
the coefficient of static friction is between the block and incline is 0.2
how large a horizontal force must push on the block if the block is to be on the verge of sliding a)up the incline and b) down the incline

So far I have ma=Fapp-(m)mg-mgsin30
where (m) is miu or friction co-efficient

ive been working on this for a long time but not sure how to get the answers
any help will be much appreciated!
 
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Welcome to PF;
Would you be able to do this if the block were not on an incline?

So far you have ##ma=F_{app}-\mu_kmg - mg\sin{\theta}## (resist the urge to put the numbers in so soon).

Is this for pushing the block up or down the slope?
Which direction does friction act?

According to the description: what is the acceleration?
 

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