A toy box is pushed along a horizontal floor through 2 m by means of a force equal to 10 N directed at an angle of 30o to the vertical. Total work done is:
Correct answer: B. 10 J
- A. 6 J
- B. 10 J
- C. 12 J
- D. 8 J
Explanation
To find the total work done when a force is applied at an angle, we use the formula W = Fdcosθ. In this case, the force applied is 10 N at an angle of 30° to the vertical. To find the horizontal component of this force, we calculate cos(60°) since the angle between the force and the direction of displacement is 90° - 30° = 60°.Thus, the work done is calculated as follows:W = (10 N)(2 m)(cos(60°)) = (10)(2)(0.5) = 10 J.Therefore, the correct answer is 10 J. The other options are incorrect as they either miscalculate the angle or the force component, leading to incorrect values for work done.
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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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