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zell_D
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Since I only got 1 reply on my old post (I think it is because my format is wrong) I am making a new post. Hopefully that is okay
a) Person A and Person B are around the same size, they play tug of war. Both pull as hard as they can but none are winning. Compare magnitude, are they same or different? If different, which one is larger? Why?
b) Person A and Person C are different in size, Person C is a child compared to Person C. They play tug of war. Both pull as hard as they can but none are winning. Compare magnitude, are they same or different? If different, which one is larger? Why?
c) Person A and Person C are still playing tug of war. Both pull as hard as they can but Person C (kid) is on a skateboard. Person A is now able to roll Person C across the floor. Compare magnitude, are they same or different? If different, which one is larger? Why?
d) Person A is now dragging Person C across the floor. Compare magnitude of forces exerted, are they same or different? If different, which one is larger? Why?
e) a small car and a big truck collides, both initially moving at 5 mph. compare the force that each exerts on the other, which is greater? which vehicle would you rather be in? why?
Newton's Third Law: F a on b = F b on a
F=ma
a) System at rest. Net force is zero. This means that the Force exerted by each person should be the same. (Because they are around the same size and neither are winning, frictional forces should also be the same)
b) System at rest. Net force is zero. This means that the Force exerted by Person C (the smaller person) is the same as Person A so that he does not get pulled towards Person A. However, I THINK I can assume that Person C's surface has a greater frictional force than Person A's surface to keep the smaller guy in the game.
c) System is NOT at rest. Net force is NOT zero. This means that the force exerted by Person A is greater than Person C. This is mainly because Person C is on a skateboard and has way less frictional force than Person A.
d) System is NOT at rest. Net force is NOT zero. Force exerted by Person A is greater than Person C. Person C is not digging into the ground for max static friction to take effect? Since kinetic friction is always lower than the max static friction. (I am REALLY lost here)
e) Same velocity means no acceleration (I am assuming the velocity stays constant, NOT SURE) so the force they apply on each other would be the same. (Even though I am really debating myself with this) Now this second part I have no idea of ________. My guess is that i would rather be in the truck instead of the small car, but I have no physical idea as to why other than that it is bigger. (Note that I haven't learned momentum yet, so any mechanics involving that would be invalid as work on my homework.)
This homework is due tuesday, I am asking in advance because I really want to understand the concept and do well in this class. thank you (and PLEASE correct my answers/explanations if they are wrong or insufficient, but remember, this is somewhat of an introductory physics course. any mechanics too advanced I probably won't have learned before)
Homework Statement
a) Person A and Person B are around the same size, they play tug of war. Both pull as hard as they can but none are winning. Compare magnitude, are they same or different? If different, which one is larger? Why?
b) Person A and Person C are different in size, Person C is a child compared to Person C. They play tug of war. Both pull as hard as they can but none are winning. Compare magnitude, are they same or different? If different, which one is larger? Why?
c) Person A and Person C are still playing tug of war. Both pull as hard as they can but Person C (kid) is on a skateboard. Person A is now able to roll Person C across the floor. Compare magnitude, are they same or different? If different, which one is larger? Why?
d) Person A is now dragging Person C across the floor. Compare magnitude of forces exerted, are they same or different? If different, which one is larger? Why?
e) a small car and a big truck collides, both initially moving at 5 mph. compare the force that each exerts on the other, which is greater? which vehicle would you rather be in? why?
Homework Equations
Newton's Third Law: F a on b = F b on a
F=ma
The Attempt at a Solution
(I am 60% sure about my answers as I just started learning this)a) System at rest. Net force is zero. This means that the Force exerted by each person should be the same. (Because they are around the same size and neither are winning, frictional forces should also be the same)
b) System at rest. Net force is zero. This means that the Force exerted by Person C (the smaller person) is the same as Person A so that he does not get pulled towards Person A. However, I THINK I can assume that Person C's surface has a greater frictional force than Person A's surface to keep the smaller guy in the game.
c) System is NOT at rest. Net force is NOT zero. This means that the force exerted by Person A is greater than Person C. This is mainly because Person C is on a skateboard and has way less frictional force than Person A.
d) System is NOT at rest. Net force is NOT zero. Force exerted by Person A is greater than Person C. Person C is not digging into the ground for max static friction to take effect? Since kinetic friction is always lower than the max static friction. (I am REALLY lost here)
e) Same velocity means no acceleration (I am assuming the velocity stays constant, NOT SURE) so the force they apply on each other would be the same. (Even though I am really debating myself with this) Now this second part I have no idea of ________. My guess is that i would rather be in the truck instead of the small car, but I have no physical idea as to why other than that it is bigger. (Note that I haven't learned momentum yet, so any mechanics involving that would be invalid as work on my homework.)
This homework is due tuesday, I am asking in advance because I really want to understand the concept and do well in this class. thank you (and PLEASE correct my answers/explanations if they are wrong or insufficient, but remember, this is somewhat of an introductory physics course. any mechanics too advanced I probably won't have learned before)