Question

A body of mass 2kg is flying horizontally with a velocity 72km/hr at a height of 10m. Find its total energy

Answer 1

Given:

Initial velocity (u) = 72km/h = 72 x1000/3600 = 20m/s

Coefficient of friction = 0.5

g = 10m/s

Final velocity = 0

a = coefficient. of friction x g

a = - 0.5 x 10

a = -5 m/s²

Now, v² - u² = 2as

0 - (20)² = 2 x -5 x s

s = - 400/-10 = 40m

                  ( I  have done it after conforming with my physics teacher)