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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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If my mass is 105 kilograms; what is my weight on Earth?
lyudmila [28]

Answer:

1029N

Explanation:

use W =mg and get answer

6 0
2 years ago
Three masses are located in the x-y plane as follows: a mass of 6 kg is located at (0 m, 0 m), a mass of 4 kg is located at (3 m
Natali [406]
<h2>Answer:</h2>

D. (1m, 0.5m)

<h2>Explanation:</h2>

The center of mass (or center of gravity) of a system of particles is the point where the weight acts when the individual particles are replaced by a single particle of equivalent mass. For the three masses, the coordinates of the center of mass C(x, y) is given by;

x = (m₁x₁ + m₂x₂ + m₃x₃) / M       ----------------(i)

y = (m₁y₁ + m₂y₂ + m₃y₃) / M       ----------------(ii)

Where;

M = sum of the masses

m₁ and x₁ = mass and position of first mass in the x direction.

m₂ and x₂ = mass and position of second mass in the x direction.

m₃ and x₃ = mass and position of third mass in the x direction.

y₁ , y₂ and y₃ = positions of the first, second and third masses respectively in the y direction.

From the question;

m₁ = 6kg

m₂ = 4kg

m₃ = 2kg

x₁ = 0m

x₂ = 3m

x₃ = 0m

y₁ = 0m

y₂ = 0m

y₃ = 3m

M = m₁ + m₂ + m₃ = 6 + 4 + 2 = 12kg

Substitute these values into equations (i) and (ii) as follows;

x = ((6x0) + (4x3) + (2x0)) / 12

x = 12 / 12

x = 1 m  

y = (6x0) + (4x0) + (2x3)) / 12

y = 6 / 12

y = 0.5m

Therefore, the center of mass of the system is at (1m, 0.5m)

7 0
3 years ago
Do someone know the answer
JulijaS [17]
Speed x time = distance
Distance divided by time = speed
500 divided by 5
Speed = 100
4 0
3 years ago
calculate the efficiency of a light bulb that had an input of 400 j transfers 100j as a light and 300j as heat.​
beks73 [17]
Efficiency = useful energy out / total energy in x 100
= 100/400 x 100
=0.25 x 100
= 25%

25%
6 0
2 years ago
Which type of reaction is shown here? 2KClO3 + heat —&gt; 2KCl + 302 endothermic reaction exothermic reaction
melamori03 [73]
The answer is "A" Endothermic. Hope that helped :)
7 0
3 years ago
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