Question

Does the KE of a car change more when it goes from 10 to 20 km/h or when it goes from 20 to 30 km/h?

Answer 1

The change in KE is more for speed change from 20 to 30 km/h

Step-by-step explanation:

Let the mass of car be m.

Speed change from 10 to 20 km/h.

     Initial speed = 10 km/hr

     Initial KE = 0.5 x m x 10² = 50 m

     Final speed = 20 km/hr

     Final KE = 0.5 x m x 20² = 200 m

     Change in KE = 200m - 50m = 150m

Speed change from 20 to 30 km/h.

     Initial speed = 20 km/hr

     Initial KE = 0.5 x m x 20² = 150 m

     Final speed = 30 km/hr

     Final KE = 0.5 x m x 30² = 450 m

     Change in KE = 450m - 200m = 250m

The change in KE is more for speed change from 20 to 30 km/h