AP EAMCET2010PhysicsWork, Power and Energy
A ball is falling freely from a height. When it reaches 10 ~m height from the ground its velocity is v₀ . It collides with the ground and loses 50 % of its energy and rises back to height of 10 ~m . Then the velocity v₀ is
Options
- A7 ~m / s
- B10 ~m / s
- C14 ~m / s
- D16 ~m / s
Correct answer
C. 14 ~m / s
Step-by-step solution
At height 10 ~m , the kinetic energy is equal to potential energy then 1 2 m v₀^2=m g h 1 2 v₀^2=9.8 10v₀^2=2 9.8 10v₀= 196 v₀=14 ~m / s