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I had a problem with Q#48 (passage 7). It was basically like there is a car moving north and then a larger truck moving south each at the same speed. They collide. After collision, the car moves east with the same speed pre-collision. What direction is the truck moving in?
I originally thought it was west, but TBR says southwest.
My first problem with this question is if they're are only moving on a north-south axis, how does the car end up going east in the first place? The explanation says that by conservation of momentum the truck must gain some westward direction, but also since the car is no longer moving on a north-south axis, the truck must have all the movement in that direction and so it's moving southwest. I don't know, for some reason the explanation just didn't make sense to me. Any help is appreciated!
Oh if someone has time in looking at Question #26 for Passage IV in that same chapter, I could use a little help in understanding that diagram and what the question is saying too. When they say spindle radius R, do they mean the radius of the lower spindle wheel in the figure, or do they mean the thicker top wheel so that the masses are held farther apart?
Thanks,
Abe
I originally thought it was west, but TBR says southwest.
My first problem with this question is if they're are only moving on a north-south axis, how does the car end up going east in the first place? The explanation says that by conservation of momentum the truck must gain some westward direction, but also since the car is no longer moving on a north-south axis, the truck must have all the movement in that direction and so it's moving southwest. I don't know, for some reason the explanation just didn't make sense to me. Any help is appreciated!
Oh if someone has time in looking at Question #26 for Passage IV in that same chapter, I could use a little help in understanding that diagram and what the question is saying too. When they say spindle radius R, do they mean the radius of the lower spindle wheel in the figure, or do they mean the thicker top wheel so that the masses are held farther apart?
Thanks,
Abe
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