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प्रश्न
Answer the following question.
Distinguish between conservative and nonconservative forces.
उत्तर
| Conservative force | Non-conservative force | |
| 1. | If work done by or against a force is independent of the actual path, the force is said to be a conservative force. | If work done by or against a force is dependent of the actual path, the force is said to be a non- conservative force. |
| 2. | During work done by a conservative force, the mechanical energy is conserved. | During work done by a nonconservative force, the mechanical energy may not be conserved. |
| 3. | Work done is completely recoverable. | Work done is not recoverable. |
| 4. | Example: gravitational force, magnetic force etc. | Example: Frictional force, air drag etc. |
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संबंधित प्रश्न
Answer the following question.
In the following table, every entry on the left column can match with any number of entries on the right side. Pick up all those and write respectively against A, B, C and D.
| Name of the force | Type of the force | ||
| A | Force due to tension in a string | P | EM force |
| B | Normal force | Q | Reaction force |
| C | Frictional force | R | Conservative force |
| D | Resistive force offered by air or water for objects moving through it. | S | Non-conservative force |
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Solve the following problem.
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Derive the expression for power in terms of F, m, and t.
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In the following table, every item on the left side can match with any number of items on the right-hand side. Select all those.
| Types of collision | Illustrations | ||
| a. | Elastic collision | i. | A ball hit by a bat. |
| b. | Inelastic collision | ii. | Molecular collisions responsible for pressure exerted by a gas. |
| c. | Perfectly inelastic collision | iii. | A stationary marble A is hit by marble B and the marble B comes to rest. |
| d. | Head-on collision | iv. | A blob of clay dropped on the ground sticks to the ground. |
| v. | Out of anger, giving a kick to a wall. | ||
| vi. | A striker hits the boundary of a carrom board in a direction perpendicular to the boundary and rebounds. | ||
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