Question

A car traveling at 6.7m/s accelerates 2.7m/s^2 to reach a speed of 11.0m/s. How long does it take for this to acceleration to occur?

Answer 1

It's another problem based around the definition of acceleration

Answer 2

Yes but this one I believe uses V=v1+at or something like that

Answer 3

well, maybe, but it's the same thing really

Answer 4

you want to use Vfinal = Vinitial + at, right ?

Answer 5

Yes

Answer 6

but I can rearrange your equation as a = (Vfinal-Vinitial)/t, which is just the definition of acceleration : )

Answer 7

However, in your question, we know a and we know Vfinal and Vinitial, so it's just a matter of rearranging the equation so that we can plug in the numbers and figure out t

Answer 8

11.0= 6.7-2.7/ t

Answer 9

no, that doesn't look right

Answer 10

6.7= 11.0-2.7/ t?

Answer 11

If you rearrange things to find t you should have t = (Vfinal-Vinitial)/a
It is important to put the brackets in

Answer 12

T= 6.7-2.7/11.0?

Answer 13

what is Vfinal ?

Answer 14

I have no idea

Answer 15

Well it is given pretty clearly in the question

Answer 16

11.0?

Answer 17

yes, Vfinal is 11
so what about Vinitial ?

Answer 18

2.7

Answer 19

are you just guessing or have you reread the question ?

Answer 20

I'm guessing because I wasn't there the day we learned this so I have no idea what any of this means

Answer 21

well that's no way to tackle problems in physics, you need to have some idea what it is all about first

but in any case, you first need to carefully read the question and absorb what it is telling you

Answer 22

Okay, would it be t= (11.0-6.7)/2.7

Answer 23

yes, that is right
I'm sorry you're having trouble with this, hope it becomes clearer for you with practice
try to keep a cool head

Answer 24

Okay so then I got 1.59s and that makes sense I think

Answer 25

yes you've got the right numbers