How Much Power Does a Sphere with a Radius of $\left( \sigma = 5.67 \times 10 ^ { - 8 } \mathrm {~W} / \mathrm { m } ^ { 2 } \cdot \mathrm { K } ^ { 4 } \right)$

question 14

Multiple Choice

How much power does a sphere with a radius of 10 cm radiate into empty space if is has an emissivity of 1.0 and is kept at a temperature of 400 K? $\left( \sigma = 5.67 \times 10 ^ { - 8 } \mathrm {~W} / \mathrm { m } ^ { 2 } \cdot \mathrm { K } ^ { 4 } \right)$

• A) 70 W
• B) 210 W
• C) 180 W
• D) 360 W
• E) 60 W

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Definitions:

Australopiths

Refers to a group of extinct hominins closely related to humans, known for their bipedal locomotion and significant role in human evolution.

Hominins

Members of the human lineage after the split from our common ancestor with chimpanzees, including all modern and extinct human species.

Upright Walking

The ability to walk on two legs with the body held vertically or nearly vertically, a characteristic primarily associated with humans.

Spider Monkey

A type of New World monkey known for its long limbs and tail, primarily living in the canopies of tropical forests.