# Physics question

Hi, please could i have help on this question? This is the question: https://app.gemoo.com/share/image-annotation/586219794155155456?codeId=Pa1ZAV0xoO4Zg&origin=imageurlgenerator

So, i have to describe the graph, i described it as constant acceleration then the ball rebounds and then it is at constant acceleration a gain however the markscheme says that the ball is decelerating at constant acceleration? I don’t understand how the ball is decelerating? The other part of the question is to draw the speed-time graph but I’m not sure how to do that? Thanks!
If you look closely at the graph at the point where the ball starts to rebound, you will see the line is not completely vertical. In fact, it has a steep negative slope, which corresponds to constant deccelaration, before the acceleration reverses direction and it begins to accelerate upwards again.
Original post by lordaxil
If you look closely at the graph at the point where the ball starts to rebound, you will see the line is not completely vertical. In fact, it has a steep negative slope, which corresponds to constant deccelaration, before the acceleration reverses direction and it begins to accelerate upwards again.

But the mark scheme says that the ball is decelerating to 0 with the same acceleration as the initial value but clearly the deceleration when it rebounds isn’t the same as the acceleration?
(edited 3 months ago)
I haven't seen the mark scheme, but what you in your first post above was that "the markscheme says that the ball is decelerating at constant acceleration". This is not the same thing as it being the same acceleration as the initial value. Both can be constant, but different in magnitude and sign.
Original post by lordaxil
I haven't seen the mark scheme, but what you in your first post above was that "the markscheme says that the ball is decelerating at constant acceleration". This is not the same thing as it being the same acceleration as the initial value. Both can be constant, but different in magnitude and sign.

Sorry, it is that the the ball is decelerating to 0 with the same acceleration as the initial value but I don’t get where this is shown on the graph? Thanks!