Correct Answer - Option 4 : for all type of forces
The correct answer is option 4) i.e. for all type of forces
CONCEPT:
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Work-energy theorem: The work-energy theorem states that the net work done by all the forces on an object equals the change in its kinetic energy.
Work done, \(W = \Delta KE = \frac{1}{2}mv^2 - \frac{1}{2}mu^2\)
Where m is the mass of the object, v is the final velocity of the object and u is the initial velocity of the object.
EXPLANATION:
- Energy and work are scalar quantities.
- So, their values depend on the sum of individual work done by the forces. If these forces cause a displacement, it will be accounted for in work done.
- The work-energy theorem can be applied in the cases of conservative forces, non-conservative forces, internal forces, external forces, and so on.
- Thus, the work-energy theorem is valid for all types of forces.
