Okeep yourself warm in the winter, you heat a solid metal ball and place it on a stand in the center of your room. the ball has a radius of 20.0 cm and an emissivity of 0.790. if your room has a temperature of 15°c, what is the net power radiated by the ball initially, when the ball's temperature is 200°c?

1.7135 x 10^10 J / s

Explanation:

R = 20 cm = 0.2 m

e = 0.79

To = 15 degree C = 15 + 273 = 288 K

T = 200 degree C = 200 + 273 = 473 K

Energy radiated per unit time = A x e x (T^4 - To^4)

Power radiated = 4 x 3.14 x 0.2 x 0.2 x 0.79 x (473^4 - 288^4)

                          = 1.7135 x 10^10 J / s

emily ruth's annual premium is $1058.50

step-by-step explanation:

emily ruth is a female of 27 years age purchasing 20 year endowment insurance with face value $25000.

from the given table,

for females, the age of a male 3 years younger should be used.

so, we have to check for 24 year male for 20 year endowment.

it is 42.34 for every $1000 face value.

for a face value of $25000,

it is 25 * 42.34 = $1058.50

∴ emily ruth's annual premium is $1058.50

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this