You are driving your car at a speed of 19.0 m/s and you hit the brakes. The car accelerates at -3.50 m/s2. (a) How long does it take the car

Question

You are driving your car at a speed of 19.0 m/s and you hit the brakes. The car accelerates at -3.50 m/s2. (a) How long does it take the car to cover 10.0 m? (b) What is the final velocity of the car?

in progress 0
Vân Khánh 4 years 2021-07-28T20:12:12+00:00 1 Answers 11 views 0

Answers ( )

  1. thuthuy
    0
    2021-07-28T20:13:49+00:00
    Reply

    Recall the formulas,

    x_f=x_i+v_it+\dfrac12at^2

    v_f=v_i+at

    (a)

    10.0\,\mathrm m=\left(19.0\dfrac{\rm m}{\rm s}\right)+\dfrac12\left(-3.50\dfrac{\rm m}{\mathrm s^2}\right)t^2

    \implies \boxed{t\approx0.555\,\mathrm s}

    (b)

    v_f=19.0\dfrac{\rm m}{\rm s}+\left(-3.50\dfrac{\rm m}{\mathrm s^2}\right)(0.555\,\mathrm s)

    \implies \boxed{v_f\approx17.1\dfrac{\rm m}{\rm s}}

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )