# Not sure how to do 2 body problem

## Homework Statement

Look below for diagram

Mass m1is on an inclined plane and weighs 1.00 kg. The inclined plane creates a 40.0 degree angle with the ground, and μk = 0.225. Mass m11 is attached to a weight hanging off the edge via pulley, called M2. M2 has a mass of 1.50kg and hangs from a height h of 50.0 cm. When the system is released from rest, how long will it take M2 to hit the floor? Assume the static frction is exceeded by the weight of M2

## Homework Equations

d=1/2(a)(t2)
f=ma (or f = mg)
f1 = MgSin∅
f2 = mg
a = net force/net weight
a = (m2g-m1gsin∅)/(m1+m2) - not sure how this was derived, was in my book

## The Attempt at a Solution

a=(1.5 kg ) (9.8 m/s2)-(1 kg ) (9.8 m/s2) sin(40)
(1 kg )+(1.5 kg )

This solution feels wrong and I'm very sure I did it wrong. Please look it over for me; I'm terribly confused by this problem.

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Sorry for bumping but still looking for help on this

gneill
Mentor

## Homework Statement

Look below for diagram

Mass m1is on an inclined plane and weighs 1.00 kg. The inclined plane creates a 40.0 degree angle with the ground, and μk = 0.225. Mass m11 is attached to a weight hanging off the edge via pulley, called M2. M2 has a mass of 1.50kg and hangs from a height h of 50.0 cm. When the system is released from rest, how long will it take M2 to hit the floor? Assume the static frction is exceeded by the weight of M2

## Homework Equations

d=1/2(a)(t2)
f=ma (or f = mg)
f1 = MgSin∅
f2 = mg
a = net force/net weight
a = (m2g-m1gsin∅)/(m1+m2) - not sure how this was derived, was in my book

## The Attempt at a Solution

a=(1.5 kg ) (9.8 m/s2)-(1 kg ) (9.8 m/s2) sin(40)
(1 kg )+(1.5 kg )

This solution feels wrong and I'm very sure I did it wrong. Please look it over for me; I'm terribly confused by this problem.
What happened to the dynamic friction between the first mass and the ramp?

List all the forces acting on the individual masses, then draw a Free Body Diagram for each. From that you should be able to write equations pertaining to each body and solve for their shared acceleration.