How Do You Calculate Mass M1 in a Frictionless Pulley System?

AI Thread Summary
To calculate mass M1 in a frictionless pulley system, start by analyzing the forces acting on both masses using free body diagrams. For mass M1, apply the equations of motion in both the x (along the plane) and y (perpendicular to the plane) directions. For mass M2, which is moving downwards with an acceleration of 3.61 m/s², use the relationship F = ma to establish a second equation. Incorporate the angle θ (30.0°) and the coefficient of kinetic friction μk (0.490) to determine the forces acting on M1. Solving these equations simultaneously will yield the value of mass M1.
jeremy04
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Homework Statement



The pulley is light and frictionless. Find the mass M1, given that M2 (6.00 kg) is moving downwards and accelerates downwards at 3.61 m/s2, that θ is 30.0°, and that μk is 0.490.

Homework Equations



F=ma
F||=mg*cos(theta)
Fper=mg*sin(theta)

The Attempt at a Solution



I have no idea where to start this problem..

I know how to find F|| and Fperendicular when there's no pulley/no friction.. no idea where to start..



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Take the freebody diagram of M1... write \Sigma\vec{F_x} = m\vec{a_x} and \Sigma\vec{F_y} = m\vec{a_y} where x is along the plane, and y is perpendicular to the plane.

similarly write an F=ma equation for M2.
 
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