Solve Forces & Inclines Homework: Find Coefficient of Friction

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In summary, the question is asking to calculate the coefficient of kinetic friction between a 3kg block and a 37 degree incline, given that the block is being pulled up the incline at a constant speed with a tension of 45N. The equation used is TsinӨ - mgsinӨ - friction = ma, with the normal force calculated as NF = mgcosӨ. After solving, the coefficient of kinetic friction is found to be μ = .4. However, it is noted that the sinӨ term in the equation is not necessary due to the tension being parallel to the incline.
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seizureboi
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Homework Statement



A 3kg block is pulled by a rope up a 37 degree incline at constant speed. If the tension in the rope is 45N and the rope is parallel to the incline, calculate the coefficient of kinetic friction between the block and the incline.

Homework Equations



a = acceleration (0 m/s2)
Ө = theta (37 degrees)
g = 9.8 m/s2
m = mass
T = Tension
μ = coefficient of friction
NF = Normal Force
friction = μNF
NF = mgcosӨ


The Attempt at a Solution



My attempt was setting up the equation: TsinӨ - mgsinӨ - friction = ma
OR 45sin(37) - (3)(9.8)sin(37) - μ(3)(9.8)cos(37) = 0
OR 27.1 - 17.7 = μ23.5
OR 9.4 = μ23.5
Finally, μ = .4

Just wondering if it's correct. =)
 
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  • #2
TsinӨ - mgsinӨ - friction = ma

You don't need a sinӨ multiplying the tension, the force of the tension is given parallel to the plane so you wouldn't need to factor an angle in, make sense?
 
  • #3
Cool, because I did try it that way and i got μ = 1.16 and I thought I was wrong so I concluded with adding a random sinӨ lol.
 

FAQ: Solve Forces & Inclines Homework: Find Coefficient of Friction

1. What is the coefficient of friction?

The coefficient of friction is a dimensionless value that represents the amount of resistance between two surfaces when they come into contact with each other. It is typically denoted by the symbol "μ" and can range from 0 (no friction) to 1 (maximum friction).

2. How is the coefficient of friction calculated?

The coefficient of friction can be calculated by dividing the force of friction by the normal force. The force of friction is the force that opposes the motion of an object, while the normal force is the force exerted by a surface on an object that is in contact with it.

3. Why is it important to find the coefficient of friction?

Finding the coefficient of friction is important in understanding the behavior of objects moving across surfaces. It helps engineers and scientists design and improve products, such as tires, brakes, and sports equipment, to ensure they have enough friction to function properly.

4. How does the angle of incline affect the coefficient of friction?

The angle of incline, or the angle at which a surface is tilted, can affect the coefficient of friction because it changes the normal force acting on an object. As the angle increases, the normal force decreases, resulting in a lower coefficient of friction. This means that it will be easier for the object to slide down the incline.

5. What are some real-life applications of finding the coefficient of friction?

Finding the coefficient of friction is important in many fields such as engineering, physics, and sports. Some real-life applications include designing efficient braking systems for cars, determining the best surface for a sports field to prevent injuries, and understanding the effects of friction on the movement of objects in space.

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