Question

A car travels at uniform acceleration over a distance of 440.0 m. Its final velocity after 20.0 s is 33.0 m/s. What is its initial velocity?

Answer 1

10. Velocity = acceleration * time = 4 * 9.81 = 39.24m/s

14. +3.0m/s (not sure)

15. Instantaneous velocity ( not sure)

18. s = 0.5 * (u+v) * t , where s=440, u = ?, v=33, t= 20
u = 11m/s

20. distance = 23 m, displacement = +1 m

25. s = ut + 0.5*a (t^2), where s=25, u =0, a=9.8, t?
25 = 0+ 4.9 (t^2)
t^2 = 5.102
t = 2.258 s

Answer 2

Since it is a uniform accelerated motion, we can use the following SUVAT equation that relates initial velocity, final velocity, time and distance covered:

`S=(1)/(2)(v_i +v_f)t`

where

S=440.0 m is the distance covered

vi is the initial velocity

vf=33.0 m/s is the final velocity

t=20.0 s is the time

Re-arranging the formula and substituting the data, we can find the initial velocity:

`v_i = (2S)/(t)-v_f=(2(440.0 m))/(20.0 s)-33.0 m/s=11.0 m/s`