Sorry about this, must seem a trivial question, but anyways here goes.(adsbygoogle = window.adsbygoogle || []).push({});

A car is travelling at 13ms^1. It is allowed to slow down natrually without appyling the brakes. The distance travelled in coming to rest is 640m.

Show that the average deceleration of the car is about 0.1ms^2.

-------------------

Ok so first of since time aint metioned i used.

v^2 = u^2 + 2as

giving me

v = 0

u =13

a = ?

s = 640

----------------------------------

v^2 = 13^2 + 2(a)640.

v^2= 13^2 +2(640)

___________

a

a * v^2 = 13^2 +2(640)

a = 13^2 +2(640)

__________

v^2

Giving me a very strange answer, no were remotely close to 0.1, ive obviously screwed up the re-arranging or used the wrong formula.

Would like a nudge in the right direction please.

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# Homework Help: Calculating deceleration

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