# How long did this car accelerate

1. Oct 18, 2007

### ryansmith885

Hello

I need help with a question i am doing: A car accelerates at 2.4ms^-2 untill it reaches a speed of 16ms^-1 how long did it accelerate for? and what distance did it travel while accelerating? could someone please help me...
Thanks
Ryan

2. Oct 18, 2007

### Sourabh N

Use Newton's laws and show ur work.(forum rule : Show people the path, don't drive them through).

3. Oct 18, 2007

### ryansmith885

um yeah thats where its gets difficult cuause i dont know how.. im not very good at physics.... mayb u could show me a couple more tips...a few formulas or something
thanx

4. Oct 18, 2007

### Sourabh N

k. one of the equation is v = u + at
where v - final vel.
u - initial vel.
a - acceleration
t - time
since its not clear(atleast to me) what is the initial vel. you can take it to be zero or report the question is wrong :)

5. Oct 18, 2007

### ryansmith885

ok thank u a lot for your help i also have another question:

the charge of one electron is -1.6x10^-19 am i correct?

so if i have a paint particle that carries 1.2 x 10^10 electrons (12000000000)what is the toatal charge it carries: i tried -1.6x10^-19 = -0.00000000000000000016 so i tried
-0.00000000000000000016 x 12000000000 electrons is this method correct? thanx again

6. Oct 18, 2007

### Bill Foster

To find the time:

v=at

To find the distance:

ax=½v²