The given diagram represents a boy lifting a block in the upward direction.The work done by the gravitational force on the block is
Correct answer: D. Negative.
- A. Zero.
- B. Positive.
- C. Variable.
- D. Negative.
Explanation
The work done by a force is calculated as the product of the force, the displacement, and the cosine of the angle between the force and the displacement. In this case, the gravitational force acts downward, while the block is moved upward. This means the angle between the force of gravity and the displacement is 180 degrees, making the work done by gravity negative. Therefore, the correct answer is that the work done by the gravitational force on the block is negative. The other options are incorrect because they do not accurately describe the direction and relationship between force and displacement in this scenario.
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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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