When a 300 N force is applied to a box weighing 600 N, the box moves 3.0 m horizontally in 20 s. What is the average power?
Correct answer: A. 45 W
- A. 45 W
- B. 90 W
- C. 900 W
- D. 1800 W
Explanation
To calculate the average power, we can use the formula: Average Power = Work / Time First, let's calculate the work done on the box. Work is given by the equation: Work = Force x Distance In this case, the force applied is 300 N, and the distance moved is 3.0 m. So, the work done is: Work = 300 N x 3.0 m = 900 J (Joules) Now, we can substitute the values into the formula for average power: Average Power = 900 J / 20 s = 45 W (Watts) Therefore, the average power exerted on the box is 45 Watts.
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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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