 #1
Karajovic
 16
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Homework Statement
Two blocks, of mass M and mass m, are in contact on a horizontal frictionless table (with the block of mass M on the left and the block of mass m on the right). A force F1 is applied to the block of mass M and the two blocks move together to the right.
a. draw a free body diagram
b. Suppose the larger block M exerts a force F2 on the smaller mass m. By Newton’s third law, the smaller block m exerts a force F2 on the larger block M. Argue whether F1 = F2 or not. Justify your reasoning.
c. Derive an expression for the acceleration of the system.
d. Derive an expression for the magnitude of the force F2 that the larger block exerts on the smaller block.
e. Choose different values of M and m (e.g. M = 2m, M = 5m, including the case M = m) and compare the magnitudes of F1 and F2.
Homework Equations
The Attempt at a Solution
a. For box of mass M:
F_{N}

F2<o>F1

Fg
For box of mass m:
F_{N}

o>F2

Fg
b. Using Newton's Third Law, for every force there is an equal reaction force. Since the box with mass M is being pushed by the force F1, doesn't that mean that it is pushing the smaller box of mass m with the same force? But this doesn't seem right because they don't have the same masses... and if F1=F2 that means the boxes wouldn't be moving right?
c. a = F_{net}/m
a = (m_{net}*a_{net})/(M+m)?
d. F2 = Ma
e. F1 = M*a, while F2 = 2m*a (I don't really understand this part)...
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