Find Frictional force on a block

Thread starter trivk96
Start date Oct 5, 2011
Tags

Block Force Frictional force

AI Thread Summary

To find the frictional force on a 9 kg block on a 30° incline with a static friction coefficient of 0.7, the relevant equations include F=ma and Ff=μ*Fn. A free body diagram can help visualize the forces acting on the block. The normal force must be calculated based on the weight of the block and the angle of the incline. The correct frictional force can be determined by applying these principles, eliminating options that do not fit the calculations. Understanding the relationship between mass, angle, and friction is crucial for solving this problem.

Oct 5, 2011

trivk96

Homework Statement

A block of mass 9 kg rests on a plane inclined
at an angle of 30◦
. The static coeﬃcient of
friction between the block and the plane is
0.7.
What is the frictional force on the block?
1. 9.36841 N
2. 76.3834 N
3. 53.4684 N
4. 44.1 N
5. 30.87

It is not # 3. I know that for sure.

Homework Equations

F=ma
F_f=μ*F_n

The Attempt at a Solution

I have no idea

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Oct 5, 2011

VACA

Have you tried drawing a free body diagram?

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