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Velocity-Time Graph question

image.jpg I have this velocity time graph and I have to find the velocity when t=1. I get 1m/s but the answers say 3m/s. What am I doing wrong?
Reply 1
Original post by Bobrey
image.jpg I have this velocity time graph and I have to find the velocity when t=1. I get 1m/s but the answers say 3m/s. What am I doing wrong?


That doesnt make any sense you are saying you have v-t graph but in image its x-t graph. can you send the whole question?
Reply 2
Original post by Reda2
That doesnt make any sense you are saying you have v-t graph but in image its x-t graph. can you send the whole question?


Sorry my post meant to to say x-t graph - the picture is correct
Reply 3
Original post by Bobrey
Sorry my post meant to to say x-t graph - the picture is correct


Yes, so velocity at t=1 is the gradient of the line starting at t=0 and ending at t=2. (I get 1 ms^-1 as well)
(edited 7 years ago)
Reply 4
Original post by Zacken
Yes, so velocity at t=1 is the area under the graph between t=0 and t=1. Which is a triangle, which has area...?


No that is not correct, the area under the graph for x-t graphs is equal to nothing, the gradient is equal to the velocity.
Reply 5
Original post by Reda2
No that is not correct, the area under the graph for x-t graphs is equal to nothing, the gradient is equal to the velocity.


Whoops, my bad. Was thinking of the wrong thing when I said area. Thanks! Will edit.

(by the way, it's not equal to nothing. :tongue: )
Reply 6
Original post by Zacken
Whoops, my bad. Was thinking of the wrong thing when I said area. Thanks! Will edit.

(by the way, it's not equal to nothing. :tongue: )


Oh really, what is it equal to?

But do you think the mark scheme is wrong? the gradient is clearly 1 and velocity is constant in that line.
Reply 7
Original post by Reda2
Oh really, what is it equal to?

But do you think the mark scheme is wrong? the gradient is clearly 1 and velocity is constant in that line.


I think so, I get 1 ms^-1 as well.
Reply 8
Original post by Zacken
I think so, I get 1 ms^-1 as well.


Just realised something, your guy in your avatar is saying something, what is it?
Reply 9
Original post by Reda2
Just realised something, your guy in your avatar is saying something, what is it?


Watch this, relevant bit is at around ~50 seconds in.
Reply 10
Original post by Zacken
Watch this, relevant bit is at around ~50 seconds in.


Find out what happens to solid water when it gets waaaarm? lol
Reply 11
Original post by Reda2
Find out what happens to solid water when it gets waaaarm? lol


It's hilarious. :rofl:

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