 Joined
 Nov 6, 2005
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 713
Ok , so there was a physics test today and there was this 5 mark question that I got wrong. In the velocitytime graph I've atttached( I know the graph isnt perfect but you get the idea); I 'm supposed to find out the accelration of the object between 0secs and 8 secs, what I did was used the formula
Isnt the speed of the object at 0 secs supposed to be 0 m/s (at least thats what the graph indicates) and since the velocity is 0m/s, the displacement at that paticular instance of time would obviously be 0. Can someone help? Tell me that she's wrong and I'm right
So since the speed of the object was 32 m/s at the end of 8 seconds and obviously the object is at rest at 0secs the answer should be 4 m/s^2, shouldn't it? But my teacher crossed out my answer and the only explanation she gives is that "since this is a velocitytime graph and the resulting line is a straight one and a straight line on a velocity time graph means no accelration"a=(v[2]v[1])/t
Where 'a'=accelration, 'v[1]'= initial velocity, 'v[2]'=final velocity & 't'=time
Isnt the speed of the object at 0 secs supposed to be 0 m/s (at least thats what the graph indicates) and since the velocity is 0m/s, the displacement at that paticular instance of time would obviously be 0. Can someone help? Tell me that she's wrong and I'm right
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