re:topper test question
Yes, your analysis is absolutely correct, the actual problem is this question is not self consistent.
However WE ARE CALCULATING THE FORCE OF FRICTION IN PRINCIPLE WHICH IS 11.9 N FOR THIS SITUATION.
As it's easy to see, we calculate the normal reaction from the frictional force of 10 N, we find the forces in a direction perpendicular to the plane won't balance the again you can conclude that it has an acceleration in perpendicular direction.
FORCES IN PERPENDICULAR AS WELL AS PARALLEL DIRECTIONS MUST CANCEL BE EQUAL EACH OTHER IF THE BLOCK IS AT REST.
PLEASE REPORT ANY DISCREPANCIES AT CONTACTUS@TOPPERLEANING.COM
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