How Did John Massis Move Two Railroad Cars with His Teeth?

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John Massis successfully moved two passenger railroad cars weighing 700 kN by using a technique that involved clamping his teeth on a bit attached to the cars and leaning backward while pushing against the railway ties. He exerted a force 2.5 times his body weight at an angle of 33 degrees. The discussion highlights the need for understanding basic physics concepts, particularly in vector mechanics, to solve the problem of calculating the cars' speed after being pulled. Participants suggest drawing a free body diagram and resolving forces into components to find acceleration. The conversation emphasizes the importance of foundational knowledge in physics for tackling such problems.
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Homework Statement


In April 1974, John Massis of Belgium managed to move two passenger railroad cars. He did so by clamping his teeth down on a bit that was attached to the cars with a rope and then leaning backward while pressing his feet against the railway ties. The cars together weighed 700 kN (about 71 tons). Assume that he pulled with a constant force that was 2.5 times his body weight, at an upward angle θ of 33˚ from the horizontal. His mass was 79 kg, and he moved the cars by 3 m. Neglecting any retarding force from the wheel rotation, find the speed of the cars at the end of the pull.

Homework Equations



Fnet = Acceleration * Mass

ax = Fcos(theta)/ M

The Attempt at a Solution


I have absolutely NO idea what to do. The professor didn't go over any problems like this DX Help!
 
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So you have never seen any problems involving a mass being accelerated by a force?
 
Simon Bridge said:
So you have never seen any problems involving a mass being accelerated by a force?
No D:I tried the formula but couldn't find acceleration
 
Try drawing a free body diagram for the situation - what are the forces on the train?
Please show your best attempt so far.
 
copypacer said:
No D:I tried the formula but couldn't find acceleration

And, like trying to solve this problem of yours:

https://www.physicsforums.com/threads/forces-problem.811390/

you'll also need to resolve some forces into their components.

I can't comment on the quality of your instruction in this subject, but it seems you are lacking knowledge of some very basic concepts in simple vector mechanics. :frown:
 
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