Power required by a boy of mass 30 kg to run up a staircase of 40 steps in 10 seconds in (Height of each step is 15 cm) (Take g = 10 m/s2)

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Q: 9 (NDA-II/2013)
Power required by a boy of mass 30 kg to run up a staircase of 40 steps in 10 seconds in (Height of each step is 15 cm) (Take g = 10 m/s2)

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,1,2,0,1,2,0

keywords: 

{'staircase': [0, 0, 0, 1], 'watt': [0, 0, 1, 5], 'steps': [0, 0, 0, 1], 'power': [24, 3, 21, 61], 'step': [2, 0, 0, 5], 'kg': [0, 1, 9, 24], 'height': [0, 0, 1, 2], 'mass': [0, 0, 2, 3], 'seconds': [3, 3, 8, 6]}

To calculate the power required by the boy to run up the staircase, we need to consider the work done and the time taken.

First, let`s calculate the work done. Work is given by the formula W = mgh, where m is the mass, g is the acceleration due to gravity, and h is the height. In this case, m = 30 kg and h is the height of each step multiplied by the number of steps (15 cm * 40 steps = 600 cm = 6 m). So, W = 30 kg * 10 m/s^2 * 6 m = 1800 Nm.

Next, we need to calculate the time taken. The question states that it takes 10 seconds to run up the staircase.

Finally, the power can be calculated using the formula P = W/t, where P is the power, W is the work done, and t is the time taken. Plugging in the values, P = 1800 Nm / 10 s = 180 W.

Therefore, the correct answer is option 2, 180 Watt.

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