The first one is(adsbygoogle = window.adsbygoogle || []).push({});

It takes 40sec for a car at rest to reach a velocity of 50 m/s. What is the car's initial velocity?

a. 0 m/s

b. 1.25 m/s

c. 1.25 m/s2

d. 50 m/s

e. 50 m/s2

I think the equation is a=v(final)-v(intial)/t

but it can't be because doesn't a(acceleration)= m/s2?

so there for you don't have the number acceleration to plug in??

Also I think I think v(final) is 50 m/s... and I don't knbow but if something

is at rest then wouldn't that be v(intial)?? Please help!!!! I am so confused! OMG

I really need to know this for a upcoming test

The next one is.

It takes 40sec for a car at rest to reach a velocity of 50 m/s. What is the car's acceleration?

I know the answer for this one but what is confusing me is that I have to choices for this answer and they are

A. 1.25 m/s

B. 1.25 m/s2

could you explain to me which one is right and how did you come to get that

this is how I solved this problem

I used a=v(final)-v(initial)/t(time)

The v(final) is 50m/s and the v(initial) is 0 because the car started at rest.

and the t is 40 (because its in seconds

I subtracted 50-0 then divded it by 40.

Last but not least:

A car starts from rest has a constant acceleration of 4m/s2. In the first 3s the car travels

a. 6m

b. 12m

c. 18m

d. 172m

I really do not understand this one. Do you use the acceleration formula.

PLEASE HELP!! I went to tutoring at my university and they didn't know how to do them either! So help me smart people lol.

Thank you in advance!

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# Homework Help: Acceleration Problems

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