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

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In summary, the conversation is about John Massis of Belgium who was able to move two passenger railroad cars by clamping his teeth on a bit attached to the cars with a rope and leaning backward while pressing his feet against the railway ties. The cars weighed 700 kN and he pulled with a constant force that was 2.5 times his body weight at an angle of 33˚ from the horizontal. His mass was 79 kg and he moved the cars by 3 m. The formula Fnet=ma was discussed and the need to draw a free body diagram and resolve forces into components was highlighted. It was also mentioned that the person asking for help may be lacking knowledge in basic vector mechanics.
  • #1
copypacer
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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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  • #2
So you have never seen any problems involving a mass being accelerated by a force?
 
  • #3
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
 
  • #4
Try drawing a free body diagram for the situation - what are the forces on the train?
Please show your best attempt so far.
 
  • #5
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:
 

1. What is the purpose of a man pulling railroad cars?

The purpose of a man pulling railroad cars is to move heavy loads of freight or passengers along a designated track. This method of transportation has been used for centuries and is still a widely used form of transportation today.

2. How much weight can a man pull when pulling railroad cars?

The amount of weight a man can pull when pulling railroad cars varies depending on the individual's strength and the conditions of the track. However, on average, a man can pull around 1 ton (2,000 pounds) on a flat, well-maintained track.

3. What techniques do men use to pull railroad cars?

There are several techniques that men use to pull railroad cars, such as using a rope or cable attached to the car, using a pulley system, or using a lever to push against the ground. These techniques help to distribute the weight and make it easier for the man to pull the cars.

4. Is it safe for a man to pull railroad cars?

When done correctly and with proper precautions, it can be safe for a man to pull railroad cars. However, it can also be dangerous, as the weight of the cars and the conditions of the track can pose risks. It is important for the man to have the necessary strength and training, as well as proper safety equipment, to ensure their safety.

5. How has technology impacted the way men pull railroad cars?

Technology has greatly impacted the way men pull railroad cars. With the invention of steam engines, trains were able to pull much heavier loads than a man ever could. And with the advancement of technology, trains have become faster, more efficient, and require less manual labor. However, there are still situations where a man may need to pull railroad cars, such as in areas where trains cannot access or for short distances.

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