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masya89 [10]
3 years ago
12

A man of mass 80 kg runs up a flight of stairs 20 m high in 10 s. (a) how much power is used to lift the man? (b) If the man’s b

ody is 25% efficient, how much power does he expend? (c) This man consumes approximately 1.05 × 107 J (2500 food calories) of energy per day while maintaining a constant weight. What is the average power he produces over a day? (d) Compare this with his power production when he runs up the stairs.
Physics
1 answer:
ad-work [718]3 years ago
7 0

Answer:

a: 1568w

Explanation:

P = F*d/t = mgd/t = 1568w

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A 97.1 kg horizontal circular platform rotates freely with no friction about its center at an initial angular velocity of 1.63 r
sammy [17]

Answer:

the final angular velocity of the platform with its load is 1.0356 rad/s

Explanation:

Given that;

mass of circular platform m = 97.1 kg

Initial angular velocity of platform ω₀ = 1.63 rad/s

mass of banana m_{b} = 8.97 kg

at distance r = 4/5  { radius of platform }

mass of monkey m_{m} = 22.1 kg

at edge = R

R = 1.73 m

now since there is No external Torque

Angular momentum will be conserved, so;

mR²/2 × ω₀ = [ mR²/2 + m_{b} (\frac{4}{5} R)² + m_{m}R² ]w

m/2 × ω₀ = [ m/2 + m_{b} (\frac{4}{5} )² + m_{m} ]w

we substitute

w = 97.1/2 × 1.63 / ( 97.1/2 + 8.97(16/25) + 22.1

w = 48.55 × [ 1.63 / ( 48.55 + 5.7408 + 22.1 )

w = 48.55 × [ 1.63 / ( 76.3908 ) ]

w = 48.55 × 0.02133

w = 1.0356 rad/s

Therefore; the final angular velocity of the platform with its load is 1.0356 rad/s

8 0
2 years ago
When energy is produced in a reaction it
goblinko [34]
The correct answer is b i believe
4 0
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As the bright sun shines upon the water, the water slowly disappears. The same sunlight gives energy to the surrounding plans to
mariarad [96]

first is physical .... sec chem

8 0
3 years ago
Which of the following is true regarding the Earth's mantle?
Brilliant_brown [7]
B) It’s material moves due to convection currents.
6 0
3 years ago
Which of the following regions of the electromagnetic spectrum has the highest energy
garri49 [273]

Answer:

B. Radiowaves

Explanation:

Radiowaves are on the higher end of the spectrum, then infrared, visible light, and UV light (which is the lowest energy)

6 0
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