Question

a car moves with a speed of 15km h-1 and another identical car is moving with the speed of 30 km h-1. compare their Kentic energy ​

Answer 1

Answer:

KE1/ KE2 = 1 / 4

Explanation:

Given,

A car moves with a speed of 15km h-1 and another identical car is moving with the speed of 30 km h-1.

To solve: Compare K.E of cars

Solution:

Since, the cars are identical, it means there masses are same i.e mass of car 1 = mass of car 2. = m (say)

For car 1:

K.E1 =  1/2 mv² = (15)²m/2 = 225m/2

For car 2:

K.E2 = 1/2mv² = (30)²m/2 = 900m/2 = 450m

Now,

Ratio of their kinetic energy = KE1 / KE2 = 225m/2*450m = 1 / 4

therefore, K.E1 / KE2 = 1 / 4