Question

A car travels a distance of 100 metre with constant acceleration and average velocity of 20 m/s.The final velocity acquired by the car is 30 m/s,the initial velocity and acceleration of the car is​

Answer 1

distance (s) = 100 m

average velocity (x) = 20 m/s

final velocity (v) = 30 m/s

let initial velocity be u

average velocity = $\frac{u+v}{2}$

$20=\frac{u+30}{2}$

40 = u + 30

u = 10

so, initial velocity (u) = 10 m/s

let us take average velocity to be the speed of the car.

time = $\frac{distance}{speed}$

time = $\frac{100}{20}$

time = 5 s

let acceleration be a

$a=\frac{v-u}{t}$

$a=\frac{30-10}{5}$

$a = \frac{20}{4}$

a = 5 m/s²

Answer 2

Answer:

initial velocity = 10m/s

acceleration of car = 4m/s²

Explanation:

given,

displacement (s) = 100m

average velocity (vₐ) = 20m/s

final velocity (v) = 30m/s

initial velocity (u) = ?

total time (t) = ?

acceleration (a) = ?

from,

average velocity = (total displacement)/(total time)

vₐ = s/t,  t = s/vₐ

⇒ t = 100/20 = 5s

from,

s = 1/2 (u+v)t

u = 2s/t - v

  = 2(100)/(5) - 30

  = 200/5 - 30

  = 40 - 30

u = 10m/s

from,

v² = u² + 2as

a = (v²-u²)/2s

  = (30² - 10²)/2(100)

  = (900 - 100)/200

   = 800/200

a  = 4m/s²