1. The problem statement, all variables and given/known data(adsbygoogle = window.adsbygoogle || []).push({});

A block of mass m1 = 280 g is at rest on a plane that makes an angle θ = 30° above the horizontal. The coefficient of kinetic friction between the block and the plane is μk = 0.10. The block is attached to a second block of mass m2 = 220 g that hangs freely by a string that passes over a frictionless and massless pulley. Find its speed when the second block has fallen 30.0 cm.

cm/s

2. The attempt at a solution

Mass 1 Mass 2

Fground=280*9.81=2746.8 N Fm2 ground=220*9.81=2158.2 N

Fgy=Fgcos(30)

=433.714 N

Fgx=Fgsin(30)

=250.405 N

Fkinetics=(.1)*(250.405)

=25.04 N

Fx= 250.405-25.04= 225.36N

Fx=max

225.36=280*ax

ax=.805 m/s2

It would be greatly appreciated if someone could please help!

Thank you!

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# Homework Help: Friction and Moving Blocks

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