The question is oversimplified, and pretty sloppy.
Relative to the Earth . . .
The Moon is in an elliptical orbit around us, with a period of
27.32... days, and with the Earth at one focus of the ellipse.
Relative to the Sun . . .
The Moon is in an elliptical orbit around the Sun, with a period
of 365.24... days, and with the Sun at one focus of the ellipse,
and the Moon itself makes little dimples or squiggles in its orbit
on account of the gravitational influence of the nearby Earth.
I'm sorry if that seems complicated. You know that motion is
always relative to something, and the solar system is not simple.
The representation of this problem is shown in Figure 1. So our goal is to find the vector
. From the figure we know that:
From geometry, we know that:
Then using
vector decomposition into components:
Therefore:
So if you want to find out <span>
how far are you from your starting point you need to know the magnitude of the vector
, that is:
</span>
Finally, let's find the <span>
compass direction of a line connecting your starting point to your final position. What we are looking for here is an angle that is shown in Figure 2 which is an angle defined with respect to the positive x-axis. Therefore:
</span>
<h2>Answer: Light waves have a redshift due to the Doppler effect
</h2>
The astronomer Edwin Powell Hubble observed several celestial bodies, and when obtaining the spectra of distant galaxies he observed the spectral lines were displaced towards the red (red shift), whereas the nearby galaxies showed a spectrum displaced to the blue.
From there, Hubble deduced that the farther the galaxy is, the more redshifted it is in its spectrum. <u>The same happens with the stars and this phenomenom is known as the Doppler effect.
</u>
This phenomenon refers to the change in a wave perceived frequency (or wavelength=color) when the emitter of the waves, and the receiver (or observer in the case of light) move relative to each other. For example, as a star moves away from the Earth, its espectrum turns towards the red.
Beta decay is very complex phenomena in natural radioactive decay. There are 3 types of Beta decay.
B+ decay (Beta plus or Beta positive or positron decay):
is the conversion of a proton into a neutron plus a positron and an electron neutrino.
B- decay (Beta negative or Beta nought):
is the conversion of a neutron into a proton plus an electron and a electron antineutrino.
Note: a positron is the a positive electron or the antiparticle of the electron.
Hope it helps
