A car traveling at 7.5 m/s accelerates 2.2 m/s^2
to reach a speed of 17.0 m/s.
How long does it take for this acceleration
to occur?
Answer in units of s

Question

A car traveling at 7.5 m/s accelerates 2.2 m/s^2
to reach a speed of 17.0 m/s.
How long does it take for this acceleration
to occur?
Answer in units of s

anonymous · Answer

s = 52.90 m

anonymous · Answer

acceleration equals change in velocity divided by change in time.

anonymous · Answer

@zainulanwar that does not properly answer the question (not only is it just plain wrong, but it doesn't offer any explanation.)

marg · Answer

how do you find the change in velocity?

anonymous · Answer

Subtraction.

marg · Answer

so 7.5 -2.2?

anonymous · Answer

2.2 is an acceleration not a velocity, you can't add or subtract unlike terms.

anonymous · Answer

Always include the units with your numbers while doing calculations, that will keep you on the right track.

marg · Answer

17m/s-7.5m/s then?

anonymous · Answer

Right. Difference is always (final) - (initial).

marg · Answer

im confused on what to do next after you find that

anonymous · Answer

Using the definition, acceleration equals change in velocity divided by change in time.
$$\large a = \frac{\Delta v}{\Delta t}$$
Solve for t by rearranging the equation
$$\large \Delta t = \frac{\Delta v}{a}$$

marg · Answer

would it be 4.318 s?

anonymous · Answer

Yes, and you can round that off to 4.3 s because you are limited to two digits of precision from the given values.

marg · Answer

thank you soooo much:)

anonymous · Answer

You're welcome. I hope it makes more sense now.

marg · Answer

it does:) i get it a lot more than i did