In the given figures, three cases are shown in which a constant force is trying to move an object from (x) to (y).The work done will be positive in case(s)
Correct answer: A. I only.
- A. I only.
- B. II only.
- C. III only.
- D. I and II.
Explanation
In physics, work done by a force on an object is positive when the force has a component in the direction of the object's displacement. In case I, the force is in the same direction as the object's movement from x to y, resulting in positive work. In case II, the force is in the opposite direction to the displacement, leading to negative work. In case III, the force is perpendicular to the direction of movement, resulting in zero work. Therefore, the correct answer is I only.
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About Work
Work is done when a force produces displacement, with its value determined by the component of force along the displacement. The topic covers positive, negative and zero work, work by variable forces from force-displacement graphs, and the connection between net work and change in kinetic energy.
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