Question

A car accelerates uniformly from 36 km/h to 72 km/h in 5 seconds. Calculate the acceleration in SI unit.

Answer 1

Answer:

u=36km/h

v=72km/h

t=5sec

a=v-u/t

a=72-36/5

a=7.2m/s2

Explanation:

Answer 2

Given:-

• Initial velocity of car = 36km/h = 36 × 5/18= 10m/s

• Final velocity of car (v) = 72km/h = 72× 5/18=20m/s.

• Time taken (t) = 5s.

To Find:-

• Acceleration (a) in SI unit.

Solution:-

We have to find the acceleration of car .

By using 1st equation of motion

⟹ v = u + at

Putting all the values which is given above.

⟹ 20 = 10 + a × 5

⟹ 20 - 10 = a×5

⟹ 10 = a×5

⟹ a = 10/5

⟹ a = 2m/s²

Additional Information !!!

✧ The rate of change of velocity at per unit time is called acceleration .

✧ SI unit of acceleration is m/s²

✧ It is vector Quantity ( both magnitude and direction)

✧ Mathematical term

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