Static Friction on an Inclined Plane: Force = mgsin30

AI Thread Summary
A block of mass m on a 30º inclined plane experiences static friction and weight as the only forces acting on it. The equilibrium condition states that the net force is zero, leading to the equation 0 = fs - mgsin30. This results in the conclusion that the force of static friction equals mgsin30. Therefore, the correct statement regarding static friction in this scenario is that fs = mg sin 30º. The discussion confirms that option D is the accurate answer.
StephenDoty
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A block of mass m is at rest on an inclined plane that makes an angle of 30º with the
horizontal, as shown in the figure. Which of the following statements about the force of
static friction is true?
A) fs > mg D)fs = mg sin 30º
B) fs > mg cos 30º E) None of these statements is true.
C) fs = mg cos 30º

because the only two forces acting on the block is fs and weight, F=0 since at rest, thus 0=fs - mgsin30 so
fs= mgsin30


So the answer is D right??
 
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Yes. Very good.
 
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