Question

A car increases its speed from 20km/hr to 40km/hr in 10 sec find it's acceleration​

Answer 1

Answer:

0.56 m/s² (approx.) or 7200 km/hr²

Explanation:

Given:

• Initial velocity (u) = 20 km/hr

• Final velocity (v) = 40 km/hr

• Time taken (t) = 10 seconds

Since 1 second = 1/3600 hr,

10 seconds = 1/360 hour

To find:

• Acceleration (a)

Method to find:

We can find the acceleration by using the 1st formula of motion.

v = u + at

⇒ 40 =  20 + (1/360)a

⇒ (1/360)a = 40- 20 = 20

⇒ a = 20 * 360

⇒ a = 7200 km/hr²

To convert to m/s², we divide it by 12960.

⇒ 7200/12960

⇒ 0.56 m/s²

Other formulae of motion:

• s = ut + 1/2at²

• v² = u² + 2as

Hence, the acceleration of the car is approximately 0.56 m/s² or 7200 km/hr². Hope it helps!