Question

Q2. A car accelerates uniformly from 20 km/h
to 40 km/h in 5 s. Calculate () the acceleration
and (ii) the distance covered by the car in that
time.
​

Answer 1

Answer:

What is Acceleration...???

Change in the velocity of an object per unit time.

Acceleration a = v-u/t

S.I Unit : m/s²

Here, u = initial velocity and v = final velocity.

a = acceleration and t = time.

i) u = 20 km/h = 5.5 m/s

v = 35 km/h = 9.7.. m/s

t = 5 second

a = v-u/t

a = 9.7 - 5.5 / 5

a = 4.2 / 5

a = 0.84 m/s²

ii) The Distance covered :

s = ut + 1/2 at²

Here, s = distance travelled by the object.

t = time

a = uniform acceleration.

s = 5.5 × 5 + 1/2 ( 0.84 ) ( 5 )²

s = 27.5 + 1/2 × 0.84 × 25

s = 27.5 + 10.5

s = 38m.

Hence, i will conclude here with final answers :

Ans i) : Acceleration = 0.84 m/s²

and ii) : s = 38m