Please HELP ME !!

Question

Please HELP ME !!

anonymous · Answer

Is this wrong in the image which i marked a red circle around it ?

anonymous · Answer

@Abhisar  and @iambatman  please help

anonymous · Answer

@UnkleRhaukus  @nincompoop  @shamil98

abhisar · Answer

No, it's correct

anonymous · Answer

how?

abhisar · Answer

What ?

anonymous · Answer

average acceleration=change in velocity/time taken

abhisar · Answer

No, average acceleration = Total displacement/Time taken

anonymous · Answer

anonymous · Answer

go through that links

anonymous · Answer

@Abhisar  are you here or not ?

abhisar · Answer

That is only for constant acceleration

abhisar · Answer

You can also calculate the answer by ur formula

abhisar · Answer

Since accn here is constant

anonymous · Answer

yes,so there is not accleration of tangent there

anonymous · Answer

right ?

abhisar · Answer

|dw:1408598946346:dw|

U=initial velocity and V =final velocity

anonymous · Answer

correct

abhisar · Answer

V-U = 10
time taken = $\sf \huge \frac{5\pi}{5}=\pi$

abhisar · Answer

average accn = 10/pi

abhisar · Answer

Got it ?

anonymous · Answer

how did you get V-U=10 ?

abhisar · Answer

You will have to add the two velocities vectorally.

Final-initial = V-U = -5j - (5J) = -10 j

anonymous · Answer

oh!!

abhisar · Answer

- denotes the direction of `change in velocity`

anonymous · Answer

@Abhisar  When we use average acceleration formula=change in displacement/time ????

anonymous · Answer

and when average acceleration=change in velocity/time

abhisar · Answer

You can use change in displacement/change in time anytime

abhisar · Answer

Second one should be used only when accn is constant

anonymous · Answer

oh!! THANK YOU SO MUCH.. @Abhisar u r the lifesaver....

abhisar · Answer

are u indian ?

anonymous · Answer

yeah