Manipal MET2016PhysicsWork, Power and Energy
A block of mass 1 kg slides down a curved track that is one quadrant of a circle of radius 1 m . Speed of the block at the bottom is 2 ~m / s . Work done by the frictional force on the block when it reaches at the bottom is
Options
- A8 J
- B-8 J
- C4 J
- D0 J
Correct answer
B. -8 J
Step-by-step solution
Given, m=1 ~kg , aligned v & =2 ~m / s R & =1 ~m W & =? aligned From energy conservation, m g h+W= 1 2 m v^2 aligned W & = 1 2 m v^2-m g h & = 1 2 1(2)^2-1 10=-8 ~J aligned