Answer:
<u><em>3.721 m/s</em></u>
This is the explanation of the ans
<span>The force of static friction F equals the coefficient of friction u times the normal force N the object exerts on the surface: F = uN. N is the centripetal force of the wall on the people; N = ma_N, where m is the mass of the people and a_N is the centripetal acceleration.
The people will not slip down if F is greater than the force of gravitation: F = uma_N > mg, or u > g/a_N.
a_N is the velocity v of the people squared divided by the radius of the room r: a_N = v^2/r.
The circumference of the room is 2 pi r = 28.3 m. So v = 28.3 * 0.8 m/sec = 22.6 m/sec.
So a_N = 114 m/sec^2.
g = 9.81 m/sec^2, so u must be at least 9.81/114 = 0.086.</span>
Any student who states that tectonic plates are too massive to move doesn't understand how much heat exists in the center of the earth. This heat is capable of moving the most massive of plates.
That's "<em><u>insolation</u></em>" ... not "insulation".
'Insolation' is simply the intensity of solar radiation over some area.
If 200 kW of radiation is shining on 300 m² of area, then the insolation is
(200 kW) / (300 m²) = <em>(666 and 2/3) watt/m²</em> .
Note that this is the intensity of the <em><u>incident</u></em> radiation. It doesn't say anything
about how much soaks in or how much bounces off.
Wait !
I just looked back at the choices, and realized that I didn't answer the question
at all. I have no idea what "1 sun" means. Forgive me. I have stolen your
points, and I am filled with remorse.
Wait again !
I found it, through literally several seconds of online research.
1 sun = 1 kW/m².
So 2/3 of a kW per m² = 2/3 of 1 sun
That's between 0.5 sun and 1.0 sun.
I feel better now, and plus, I learned something.
