A crate moves 10m to the right on a horizontal surface as a woman pulls on it with a 10N force. Rank the situations shown below according to the work done by her force from least to greatest.
Correct answer: A. 3, 2, 1
- A. 3, 2, 1
- B. 2, 3, 1
- C. 2, 1, 3
- D. 1, 3, 2
Explanation
1. Force and displacement are parallel to each other. So, θ =0, cosθ = 1 hence W1 = F2. Force and displacement are making some angle "θ"W2 = Fdcosθ3. Force and displacement are perpendicular to each other. So, θ = 90°, cos90° = 0 so W=0W3 < W2 < W1
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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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