- #1
- 156
- 10
This is a 2d collision that conserves momentum. Make this the basis of your explanation. Is E consistent with momentum conservation?Homework Statement
in the attached file
Homework Equations
Momemtum = mass - velocity
The Attempt at a Solution
I solved it E. Since object 2 has the larger mass, the effect is less and will move backwards a little bit.
I am not sure. But no It should have y and x components , I guess.This is a 2d collision that conserves momentum. Make this the basis of your explanation. Is E consistent with momentum conservation?
You guess correctly. The total initial momentum has x and y components, therefore the total final momentum must have x and y components. You need to reconsider your answer.I am not sure. But no It should have y and x components , I guess.
The total momentum is the vector sum of the momenta of the two balls. You don't have to write equations, but you need to be systematic. Not only you have to find the right answer, but also you have to exclude the others as incorrect. Fill in the blanks.
1. The total initial momentum is ____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
2. Therefore the total final momentum must be
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
3. The choice that is consistent with (2) is ____C_____ .
4a. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4b. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4c. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4d. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
I think it is 2. Is it like vector addition?You are making progress. This exercise should be an eye-opener for you because it seems you have not grasped what momentum conservation means. It means that the total momentum vector must be the same before and after the collision. Two vectors are the same if and only if they have the same magnitude and point in the same direction. In (1) you say that the total momentum before the collision points to the left (negative) and up (positive). In (2) you say that the total momentum after the collision points to the right (positive) and down (negative). These two do not point in the same direction, therefore they are not the same before and after the collision, therefore your answers in (1) and (2) are inconsistent with momentum conservation. You need to reconsider. Hint: One of the answers, (1) or (2), is correct but the other is not. Which one?
(2) is what? Correct or incorrect? Yes, it is exactly like vector addition. As I indicated in post #6,I think it is 2. Is it like vector addition?
The total momentum is the vector sum of the momenta of the two balls.
2 is the right one. Yes, sorry did not concentrate.(2) is what? Correct or incorrect? Yes, it is exactly like vector addition. As I indicated in post #6,
All blanks are the same as 2. Choices ABDE except CThe total momentum is the vector sum of the momenta of the two balls. You don't have to write equations, but you need to be systematic. Not only you have to find the right answer, but also you have to exclude the others as incorrect. Fill in the blanks.
1. The total initial momentum is ____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
2. Therefore the total final momentum must be
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
3. The choice that is consistent with (2) is ____C_____ .
4a. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4b. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4c. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
4d. Choice _____ is inconsistent because the total final momentum is supposedly
____________ (positive/negative/zero) in the x-direction and ____________ (positive/negative/zero) in the y-direction.
Thank you for your help and time!OK. I think you got it.