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faltersainse [42]

2 years ago

7

The stair stepper is a novel exercise machine that attempts to reproduce the work done against gravity by walking up stairs. Wit

h each step, Brad (of mass 60 kg) simulates stepping up a vertical distance of 0.2 m with this machine. If Brad exercises for 13 min per day with a stair stepper at a frequency of 50 steps per minute, what total work he does he do each day

1 answer:

Delicious77 [7]2 years ago

7 0

Answer:

W = 76518 J = 76.518 KJ

Explanation:

First, we will find the total number of steps taken by Brad, as follows:

$No.\ of\ steps = n = (13\ min)(50\ steps/min) = 650\ steps\\$

Now, we will calculate the height covered while covering these number of steps:

$Height\ Covered = H = (n)(Height\ for\ 1\ step)\\\\H = (0.2\ m/step)(650\ steps)\\H = 130\ m$

Now, we will calculate the amount of work done while covering this distance:

$Work = W = mgH = \\W = (60\ kg)(9.81\ m/s^2)(130\ m)$

<u>W = 76518 J = 76.518 KJ</u>

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3 years ago

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Answer: $0.8\ mm$

Explanation:

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The Spanish flu pandemic of 1918, the deadliest in history, infected an estimated 500 million people worldwide about one-third of the planet’s population and killed an estimated 20 million to 50 million victims, including some 675,000 Americans. The 1918 flu was first observed in Europe, the United States and parts of Asia before swiftly spreading around the world. At the time, there were no effective drugs or vaccines to treat this killer flu strain. Citizens were ordered to wear masks, schools, theaters and businesses were shuttered and bodies piled up in makeshift morgues.

Does this sound familiar?

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