A ball acceleration and velocity vectors

AI Thread Summary
The discussion focuses on the behavior of a ball thrown vertically upward and its velocity and acceleration vectors during flight. The key point is that while the ball ascends, the velocity vector points upward and the acceleration vector, due to gravity, points downward. As the ball descends, both the velocity and acceleration vectors point downward. Thus, the correct answer to the homework question is A, indicating that the vectors are initially in opposite directions and then in the same direction. The conversation emphasizes understanding the relationship between velocity and acceleration in the context of gravitational force.
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Homework Statement



a ball is thrown vertically upward and then comes back down. during the flight up and down the velocity and acceleration vectors are
A first in opposite directions then in the same
B always in the same direction
C first in the same then in opposite directions
D always in opposite directions-no

The Attempt at a Solution


ikm guessing a because the acceleration vector is gravity
 
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You seem to be on a roll here.
Well, I'm in a good mood so I'll take this one on as well. o:)

When the ball is going up, in which direction does the velocity vector point?
And in which direction does the gravity vector point?

After that, when the ball is going down, in which direction does the velocity vector point?
And in which direction does the gravity vector point?
 


I like Serena said:
You seem to be on a roll here.
Well, I'm in a good mood so I'll take this one on as well. o:)

When the ball is going up, in which direction does the velocity vector point? up
And in which direction does the gravity vector point? down

After that, when the ball is going down, in which direction does the velocity vector point? down
And in which direction does the gravity vector point?down

so it would be A
 
Yay! :approve:
 
yay! your the best homework helper ever.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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