Static friction Problem?

Question

The coeffcient of static friction between the
3.99 kg crate and the 34 degree incline is 0.336.
The acceleration of gravity is 9.8 m/s^2 .

What minimum force F must be applied to
the crate perpendicular to the incline to pre-
vent the crate from sliding down the incline?
Answer in units of N.

Answer 1

The normal force times the coefficient of friction must offset the pull from gravity.

Parallel force, p:

sin(34)=p/(3.99*9.81)
compute p

then (Cos(34)*3.99*9.81+F)*.3336
=p

F=33.16 N

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