If the Sun were to turn into a black hole, or be replaced by a black hole
with the same mass as the Sun, then Earth would continue to orbit it
as usual. (But it would be very cold and dark around here.)
Answer:
775.48 W
Explanation:
given,
diameter of disk = 0.6 cm
length of the disk = 0.4 m
T₁ = 450 K T₂ = 450 K T₃ = 300 K
= 1.33
now,
the value of view factor (F₁₂)corresponding to 1.33
F₁₂ = 0.265
F₁₃ = 1 - 0.265 = 0.735
now,
net rate of radiation heat transfer from the disk to the environment:

= 2 F₁₃ A₁ σ (T₁⁴ - T₃⁴)
= 2 x 0.735 x π x (0.3)² x (5.67 x 10⁻⁸ W/m²) (450⁴ - 300⁴)
= 775.48 W
Net radiation heat transfer from the disks to the environment = 775.48 W
Apple, Pear, hourglass, bodybuilder, and rectangle.
1, 2 & 4 are going to be the the correct answer for the question
Answer A material that decreases the rate of a reaction. The amount of energy that reactants must absorb before a chemical reaction will start also called free energy of activation. What role does activation energy pay in chemical reactions? Activation energy is the energy absorbed before it can start a chemical reaction.
Explanation: