To calculate the volume of a rectangular, we have to multiply the value of height, length and width.
8x5x4 = 160 cm ^3
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:
17.4 cm
Explanation:
Power of lens = +1.75 diopters
Focal length of lens

This is a convex lens as focal the diopter given is positive which makes the focal length positive. Image distance will be negative.
v = -25

∴ The new near point is 17.4 cm
Answer: i think it’s plant and glass
Explanation:
Answer:
Explanation:
This figure given is the frequency; 2 times per second represents frequency.
What is frequency?
- It is the number of times per seconds something goes past or around another.
it is expressed as:
Frequency = 
where n is the number of turns
t is the time taken
Therefore, the Barber spinned him 2 times in 1 second.
The period is the inverse of frequency. It is the time taken for a body to go through a point;
Period =
=
s