At which angle is the work done equal to half of its maximum value?
Correct answer: B. 60°
- A. 30°
- B. 60°
- C. 45°
- D. 90°
Explanation
The work done by a force is given by the formula W=Fdcosθ, where F is the magnitude of the force, d is the displacement, and θ is the angle between the force and the displacement vectors. The maximum value of W occurs when cosθ=1, which happens when θ=0°. Half of the maximum value occurs when cosθ=1/2 , which happens when θ=60°. Therefore, the correct option is (b) 60°.Incorrect Options Explanation:(a) 30°: This angle corresponds to a different fraction of the maximum value of work done.© 45°: this doesn't correspond to half of maximum value.(d) 90°: When the angle is 90°, the work done is zero because the force and displacement vectors are perpendicular.
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About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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