Answer:
Explanation:
The apparent brightness follows an inverse square law, therefore we can write:
where I is the apparent brightness and r is the distance from the Sun.
We can also rewrite the law as
(1)
where in this problem, we have:
apparent brightness at a distance 
, where
million km
We want to estimate the apparent brightness at 
, where is ten times , so
Re-arranging eq.(1), we find 
:
Hey there!
The answer would be B. The sound moves from air to water.
Sound travels through different mediums. It goes fastest in solids, a little slower in liquids, and slowest in air. Sound is a very fast wave, but remember that mediums can differ that. In a vacuum space, there is no sound at all. (ex. outer space)
Hope this helps !
A plane flying initially at 100 m/s uses an acceleration of 5 m/s² to reach a velocity of 150 m/s in 10 seconds.
<h3>What is acceleration?</h3>
Acceleration is the change in velocity over time.
A plane is flying initially at 100 m/s (u) and it accelerates to 150 m/s (v) in 10 s (t). We can calculate its acceleration using the following expression.
a = v - u / t = (150 m/s - 100 m/s) / 10 s = 5 m/s²
A plane flying initially at 100 m/s uses an acceleration of 5 m/s² to reach a velocity of 150 m/s in 10 seconds.
Learn more about acceleration here: brainly.com/question/14344386
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The distance travelled by the ball that is thrown horizontally from a window that is 15.4 meters high at a speed of 3.01 m/s is 5.34 m
s = ut + 1 / 2 at²
s = Distance
u = Initial velocity
t = Time
a = Acceleration
Vertically,
s = 15.4 m
u = 0
a = 9.8 m / s²
15.4 = 0 + ( 1 / 2 * 9.8 * t² )
t² = 3.14
t = 1.77 s
Horizontally,
u = 3.01 m / s
a = 0 ( Since there is no external force )
s = ( 3.01 * 1.77 ) + 0
s = 5.34 m
Therefore, the distance travelled by the ball before hitting the ground is 5.34 m
To know more about distance travelled
brainly.com/question/12696792
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