More frustrating force problems,

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SUMMARY

The discussion addresses two physics problems involving force calculations. The first problem involves a chair with a mass of 10.1 kg being pushed with a force of 47.7 N at an angle of 39.6 degrees below the horizontal, requiring the calculation of the normal force exerted by the floor. The second problem involves an 87.7 kg man who falls from a height of 2.89 m and comes to rest after moving an additional 0.60 m, necessitating the calculation of the average force his feet exert on the ground during deceleration. Key concepts include free body diagrams and Newton's second law.

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  • Understanding of free body diagrams (FBD)
  • Knowledge of Newton's second law of motion
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More frustrating force problems, please help!

Homework Statement


1.)A chair of mass 10.1 kg is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force of 47.7 N that is directed at an angle of 39.6 degrees below the horizontal and the chair slides along the floor. Calculate the normal force that the floor exerts on the chair

2.)A 87.7 kg man steps off a platform 2.89 m above the ground. He keeps his legs straight as he falls, but at the moment his feet touch the ground his knees begin to bend, and, treated as a particle, he moves an additional 0.60 m before coming to rest. Treating our rigid legged friend as a particle, what is the average force his feet exert on the ground while he slows down?

Note: Assume the acceleration while he is slowing down is constant


Homework Equations


For Question 1
u nid to find the sum of forces in the x and y directions respectively
for question 2
remember gravity


The Attempt at a Solution


i drew a free body diagram, i suggest u do d samem maybe there was a flaw in mine.
 
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For the first question, you don't really need to consider the forces in the x direction. What does your FBD look like for the y directions? This should be enough to sum up the forces.

For question 2 you need to consider the acceleration that's exerted on the person to make him stop in the given distance, and remember Newton's second law.
 

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