If a body of mass 2kg is raised vertically through 2m, then the work done will be:
Correct answer: B. 39.2 J
- A. 38.2 J
- B. 39.2 J
- C. 392.1 J
- D. 3.92 J
Explanation
When a body is raised vertically, the work done against gravity is given by the formula:Work = Force × Distance × cos(θ).In this case, the force is the weight of the body (mg), where m is the mass (2 kg) and g is the acceleration due to gravity (approximately 9.8 m/s²). The distance is 2 meters, and the angle θ between the force and displacement is 0° (since they are in the same direction).So, Work = (2 kg) × (9.8 m/s²) × (2 m) × cos(0°) = 39.2 J.
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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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