Answer:
power emitted is 1.75 W
Explanation:
given data
length l = 5 cm = 5 ×
m
diameter d = 0.074 cm = 74 ×
m
total filament emissivity = 0.300
temperature = 3068 K
to find out
power emitted
solution
we find first area that is π×d×L
area = π×d×L
area = π×74 ×
×5 ×
area = 1162.3892 ×
m²
so here power emitted is express as
power emitted = E × σ × area × (temperature)^4
put here all value
power emitted = 0.300× 5.67 × 1162.3892 ×
× (3068)^4
power emitted = 1.75 W
<u>Answer:</u>
The amount of the lighted side of the moon you can see is the same during "how much of the sunlit side of the moon faces Earth".
<u>Explanation:</u>
The Moon is in sequential rotation with Earth, and thus displays the Sun, the close side, always on the same side. Thanks to libration, Earth can display slightly greater than half (nearly 59 per cent) of the entire lunar surface.
The side of the Moon facing Earth is considered the near side, and the far side is called the reverse. The far side is often referred to as the "dark side" inaccurately but it is actually highlighted as often as the near side: once every 29.5 Earth days. During the New Moon the near side becomes blurred.
Answer:
P = 251, 3 W
Explanation:
The intensity is defined as the power emitted per unit area
I = P / A
Since sound is distributed in all directions spherical shape, the area of a sphere is
A = 4π r²
let's clear the power and replace
P = I A
P = I (4π r²)
let's calculate
P = 5.00 (4π 2²)
P = 251, 3 W