Answer:
b) Betelgeuse would be 
times brighter than Sirius
c) Since Betelgeuse brightness from Earth compared to the Sun is 
the statement saying that it would be like a second Sun is incorrect
Explanation:
The start brightness is related to it luminosity thought the following equation:
(1)
where 
is the brightness, 
is the star luminosity and 
, the distance from the star to the point where the brightness is calculated (measured). Thus:
b) 
and 
where 
is the Sun luminosity (
) but we don't need to know this value for solving the problem. 
is light years.
Finding the ratio between the two brightness we get:
c) we can do the same as in b) but we need to know the distance from the Sun to the Earth, which is 
. Then
Notice that since the star luminosities are given with respect to the Sun luminosity we don't need to use any value a simple states the Sun luminosity as the unit, i.e 1. From this result, it is clear that when Betelgeuse explodes it won't be like having a second Sun, it brightness will be 5 orders of magnitude smaller that our Sun brightness.
Answer:
1. Static electricity has two charges magnetism has two poles.
2. Same charges and same poles repel and opposite charges and poles attract.
3. Static electricity is produced by charges(at rest) Magnetism is produced by charges(moving with uniform speed)
<span>m1v1 + m2v2 = (m1+m2)*(-vf)
6*5 + 2*v2 = (6 + 2)*(-2)
v2 = -16/2 = -8 m/s i</span>
The wavelength of a sound wave is related to its frequency by the relationship:
where
f is the frequency
v is the speed of the wave
is the wavelength
The wave in our problem has wavelength of
and speed of
(this is the speed of sound in air), therefore its frequency is
And the period of the wave is equal to the reciprocal of its frequency:
Its 1.73793151243 as a whole but if rounded it is 1.74
