A particle moves with a velocity 6i-4j+3k ms-1 under the influence of a constant force F=20i+15j-5k N. The instantaneous power applied to particle is:
Correct answer: A. 45 Js-1
- A. 45 Js-1
- B. 35 Js-1
- C. 25 Js-1
- D. 195 Js-1
Explanation
The instantaneous power applied to a particle can be calculated using the formula:Power = Force · VelocityGiven that the velocity of the particle is 6i - 4j + 3k m/s and the force acting on it is 20i + 15j - 5k N, we can substitute these values into the formula:Power = (20i + 15j - 5k) · (6i - 4j + 3k)To calculate the dot product, we multiply the corresponding components and sum them up:Power = (20 * 6) + (15 * -4) + (-5 * 3)= 120 - 60 - 15= 45Therefore, the instantaneous power applied to the particle is 45 watts (W) or J/s
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About Power
Power is the rate at which work is done or energy is transferred, with average power calculated over a time interval and instantaneous power found from P = Fv when force and velocity are aligned. Work includes units, mechanical efficiency, and the distinction between power and total work or energy.
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