Anonymous
Anonymous asked in Science & MathematicsMathematics · 1 decade ago

If the car goes from 0 to 80 mph in six seconds with constant acceceleration, what is that acceceleration?

If the car goes from 0 to 80 mph in six seconds with constant acceceleration, what is that acceceleration?

I asked "2" time but there was a good answer. This is calculus related to physical problem. The question is RIGHT, I did check before posting.

the right answer is 19.55 ft/s^2 ( in the back of the text book)

mph = mile per hour

-----------

If someone how to get 19.55 ft/s^2, please help me

Update:

It was written correctly 100% from the college text book

5 Answers

Relevance
  • raj
    Lv 7
    1 decade ago
    Favorite Answer

    80 miles per hour=80*1.47 ft/sec

    =117.6 ft /sec

    time taken=6 sec

    so acceleration=117.6/6=19.55 ft/sec^2

    you post the question wrongly and you talk about answer not beingimportant and the steps should be right.

    lasttime you had posted the same problem and giventhe speed as 80 kmph

    people living in glass houses shouldnot throw stones

  • Anonymous
    1 decade ago

    v = u + at

    Since u = 0

    v = 80 mph

    t = 6 s

    a = ?

    80 mph= a x 6

    80 mph = 80/ 60 x 60 miles per second

    and 80 miles = 422400 ft

    now

    422400 /3600 = 6a

    4224/36 = 6a

    117.3333 = 6a

    a = 117.333/6

    therefore a = 19.55 ft / second square

  • 1 decade ago

    I think you're having trouble with the units. The question is stated in several different units and your answer needs to come out in yet another unit. So simply integrating 0 to six and expecting the answer to come out in miles per hour won't do it, becuase the 0 to 6 is in seconds, not hours. And then the answer, to further complicate matters, comes out in feet per second, so when you get your answer in terms of mph, you then have to translate it into feet per second to see if it is right or not.

    My suggestion .. use dimensional analysis to translate everything in this question to feet per second, since that's the terms of the answer, then work it out like usual.

  • 1 decade ago

    a=(v-u)/t

    a= (80-0)/6

    i cant get 19.55ft/s^2

    but thats the formula

    just remember what units you are using - you use mph and feet per second in the question - that may confuse you

  • How do you think about the answers? You can sign in to vote the answer.
  • 1 decade ago

    iz don't know but nice to meet you

Still have questions? Get your answers by asking now.