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Maths/Physics Help!

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Guys I’m being really dumb today and I can’t figure this question out, help me please
Reply 1
For distance I put 32m initially but that was wrong, and I put -2 and -8 for the displacement but they weren’t right
What’s your working for those questions?
Reply 3
Original post by 0ptics
What’s your working for those questions?


To find the distance, I tried to find the area, so I did 8x8/2 and I got 32m,

For the displacement I have no working out tbh
Distance is always the area under a velocity time graph. So distance= sum of the area of the two triangles = (6x6)/2 + 2x2/2 = which is 8m

Displacement is essentially distance but with a direction, so since it is moving backwards (negative velocity) from 6-8 seconds, then it will be the area of the big triangle, minus the area of the small triangle (from 6-8s). This would be 6- (2x2)/2= 4m
(edited 2 years ago)
Reply 5
Original post by chinjyanson
Distance is always the area under a velocity time graph. So distance= sum of the area of the two triangles = (6x6)/2 + 2x2/2 = which is 8m

Displacement is essentially distance but with a direction, so since it is moving backwards (negative velocity) from 6-8 seconds, then it will be the area of the big triangle, minus the area of the small triangle (from 6-8s). This would be 6- (2x2)/2= 4m


Thank you so much, I understand all of this, I just can’t see the two triangles, I can only see one big one
Reply 6
Original post by chinjyanson
Distance is always the area under a velocity time graph. So distance= sum of the area of the two triangles = (6x6)/2 + 2x2/2 = which is 8m

Displacement is essentially distance but with a direction, so since it is moving backwards (negative velocity) from 6-8 seconds, then it will be the area of the big triangle, minus the area of the small triangle (from 6-8s). This would be 6- (2x2)/2= 4m


Also how is the distance 8m because 6x6/2 is equal to 18 and 2x2/2 is 2m so wouldn’t it be 20m
Reply 7
Original post by chinjyanson
Distance is always the area under a velocity time graph. So distance= sum of the area of the two triangles = (6x6)/2 + 2x2/2 = which is 8m

Displacement is essentially distance but with a direction, so since it is moving backwards (negative velocity) from 6-8 seconds, then it will be the area of the big triangle, minus the area of the small triangle (from 6-8s). This would be 6- (2x2)/2= 4m


Omg I see the two triangles now tysm
Original post by zainabxxx
Also how is the distance 8m because 6x6/2 is equal to 18 and 2x2/2 is 2m so wouldn’t it be 20m

Oh yes my bad it is.
Reply 9
Original post by chinjyanson
Oh yes my bad it is.


The displacement is not 4m
Original post by zainabxxx
H17096EBF-0C3A-4BDB-90CD-7A22DB71F69F.jpg.jpeg

Guys I’m being really dumb today and I can’t figure this question out, help me please

What is the average speed of the particle?
Original post by chinjyanson
So distance= sum of the area of the two triangles = (6x6)/2 + 2x2/2 = which is 8m

18+2 isn't 8.
Original post by chinjyanson
Displacement is essentially distance but with a direction, so since it is moving backwards (negative velocity) from 6-8 seconds, then it will be the area of the big triangle, minus the area of the small triangle (from 6-8s). This would be 6- (2x2)/2= 4m

I agree with the logic, but the equation is wrong.
Original post by zainabxxx
Also how is the distance 8m because 6x6/2 is equal to 18 and 2x2/2 is 2m so wouldn’t it be 20m

Yes.

For the displacement, an easy way is average speed * time.
(edited 2 years ago)
Reply 13
Original post by RogerOxon
Yes.

For the displacement, an easy way is average speed * time.


That would give you the distance, I think you mean average velocity!
Original post by chinjyanson
Distance is always the area under a velocity time graph.

In future please read the forum rules before posting - we do not give solutions
Original post by zainabxxx
That would give you the distance, I think you mean average velocity!

Perhaps, depending on how you define terms.

Both average speed and velocity would be useful here.
(edited 2 years ago)
Original post by zainabxxx
That would give you the distance, I think you mean average velocity!

No, velocity is a vector quantity meaning that it has a direction. This means that velocity can have a negative direction. Apply this to the formula and you get a negative distance, which is wrong as distance is scalar, hence it can’t have a negative value.

Average speed is the correct term here.

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