Friction and tension force- mass

AI Thread Summary
The discussion revolves around calculating the mass of a cow, Brisket, being pulled up a ramp with friction. The ramp is inclined at 26.6° with a coefficient of kinetic friction of 0.674, and a tension force of 5060.8N is applied. The user initially attempted to use a specific equation but arrived at an incorrect mass of 916.31 kg. Participants suggest analyzing the forces acting on Brisket and applying Newton's second law to find the net force. The key is to express the friction in terms of the normal force and to sum the forces parallel to the incline to solve for the mass accurately.
Paulbird20
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Friction and tension force-- mass

Homework Statement



In the real world, ramps aren't frictionless, so I had to drag Brisket up a ramp, slanted at 26.6° from the ground, that had a coefficient of kinetic friction = 0.674. I applied a tension force FR=5060.8N to my pet cow using the rope. Brisket moved up the ramp with an acceleration of magnitude 1.54m/s2. With this information, including friction on the ramp, what is Brisket's mass (in kg)?

Homework Equations


T= Uk*m*g/cos(angle)+Uksin(angle)
Fnet= ma


The Attempt at a Solution



I attempted to use the first equation

5060.8 = .674 * m * 9.8 / (cos(26.6)+ .674 sin(26.6)

using this equation i got 916.31 kg which is incorrect

any tips would be much appreciated thanks
 
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Paulbird20 said:

Homework Equations


T= Uk*m*g/cos(angle)+Uksin(angle)
Where does this formula come from?

Instead, just analyze the forces acting on the cow and apply Newton's 2nd law:
Fnet= ma
 


ok so the forces i have acting on the cow are:

mgsin(angle)
mgcos(angle)
mg
Friction(going up the incline)
N(force)

im not sure how to arrive at Fnet because i need the mass to be able to get the components of it
 


Paulbird20 said:
ok so the forces i have acting on the cow are:

mgsin(angle)
mgcos(angle)
mg
The weight (mg) can be broken into components.
Friction(going up the incline)
Express the friction in terms of the normal force and μ. Which way does it act?
N(force)
Don't forget the tension force.

im not sure how to arrive at Fnet because i need the mass to be able to get the components of it
Find Fnet by adding up all the force components parallel to the incline. (There are three such components.) Set up an equation using Newton's 2nd law and solve for the mass.
 
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