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Benzoate
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Homework Statement
A mass m slides on a plane. It is attached to an inextensible massless string, the other end of which is attach to an equal mass. you can assume the pulley is frictionless , but that the surface has a coefficient of static friction. and the frictional force has the form F(f). As you increase the angle theta, at what angle will the block stop moving?
Homework Equations
The Attempt at a Solution
Relevant forces: Frictional force, normal force, gravitational force and tension force. I think that I need to set my acceleration to zero since the block stops moving. Forces for both masses will be in the x and y directions:
x-component: For m1: T-m*g*mu*cos(theta)=m*dv/dt
For m2: ma=0, since m2 hangs vertically from the pulley
y-component: For m1: I don't think there is a tension force in the y direction , therefore, the forces in the y direction are just the normal force exerted by the inclined plane and the gravitational force:ma = 0 since the mass is not accelerating in the y-direction: N-m*g*mu*cos(theta)=0 ==> N=mg*mu*cos(theta)
For m2, I'm not sure whether to include the tension acting on m1 and m2 or just the tension acting on m2. I know both masses have the same tension, since the pulley is massless. I think both masses would have the same acceleration since both masses are attached to the same string. well here is what I think is the correct force equation for m2:
for m2: T-m2*g=m*a