What are the reaction forces to the external forces on the wagon in (b)?

AI Thread Summary
The discussion focuses on identifying the reaction forces exerted by a wagon under external forces, particularly in scenario (b) on Earth. Key points include the wagon exerting downward forces on the Earth due to contact and gravitational attraction, as well as upward forces due to contact. There is uncertainty regarding whether the wagon exerts an upward force to the left on the handle, with some participants suggesting that this could be a trick question. Additionally, the conversation emphasizes the importance of separating different exercises for clarity. The thread illustrates the complexities of analyzing forces in physics problems.
Morrissey
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Homework Statement


One or more external forces are exerted on each object enclosed in a dashed box shown in the figures below. Identify the reaction to each of these forces, assuming that (b) occurs on Earth. Select all that apply.
SDDrMtd.png


(b) the wagon exerts a force

· downward on the Earth due to contact
· downward on the Earth due to gravitational attraction
· upward on the Earth due to gravitational attraction
· upward to the left on the handle (?)
· upward on the Earth due to contact

(My choices in underline)
3. The Attempt at a Solution

The main question I have about this problem is whether the wagon exerts a force upwards to the left on the handle. I thought that the wagon would exert a force downwards to the left on the handle, but this isn't an answer choice, so I thought that selection would be a trick question.

Thanks in advance!
 
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Hi Morrissey, :welcome:

(better to keep one exercise per thread -- less confusing)

Thread 1: I think I agree with your thinking.

Thread 2: when ##m_1## is at rest, the maximum friction force is ##\mu_s N = \mu_s m_1 g##; you must first check if the driving force ##m_2 g## can exceed this.
 
Note: the second exercise has been removed from this thread. The OP is invited to post it in a separate thread.
 
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