The answers are B, C, E and F.
Atoms from an element is mostly made of protons, neutrons, and electrons. Proton numbers are like a class number for each element. Each element has their own and they're all different. And the number of protons are equal to the number of electrons. Therefore, B is correct.
Isotopes. It's different atoms from a same element that has the same number of protons but different number of neutrons. For example in hydrogen, there's 3 Isotopes for hydrogen. Therefore, C is correct.
Again, proton for the same element is never changed, even if they're different Isotopes. So, E is correct.
Isotopes, again, different elements may have different Isotopes. Some has only 1, others may have a few or more. So, F is correct too.
Answer:
The units of the orbital period P is <em>years </em> and the units of the semimajor axis a is <em>astronomical units</em>.
Explanation:
P² = a³ is the simplified version of Kepler's third law which governs the orbital motion of large bodies that orbit around a star. The orbit of each planet is an ellipse with the star at the focal point.
Therefore, if you square the year of each planet and divide it by the distance that it is from the star, you will get the same number for all the other planets.
Thus, the units of the orbital period P is <em>years </em> and the units of the semimajor axis a is <em>astronomical units</em>.
Light energy is defined as how nature moves energy at an extremely rapid rate, and it makes up about 99% of the body's atoms and cells, and signal all body parts to carry out their respective tasks. An example of light energy is the movement of a radio signal.
Answer:
If the radio wave is on an FM station, these are in Megahertz. A megahertz is one ... Typical radio wave frequencies are about 88~108 MHz .
Explanation:
To calculate the wavelength of a radio wave, you will be using the equation: Speed of a wave = wavelength X frequency.
Since radio waves are electromagnetic waves and travel at 2.997 X
10
8
meters/second, then you will need to know the frequency of the radio wave.
If the radio wave is on an FM station, these are in Megahertz. A megahertz is one million hertz. If the radio wave is from an AM radio station, these are in kilohertz (there are one thousand hertz in a kilohertz). Hertz are waves/second. Hertz is usually the label for the frequency of electromagnetic waves.
To conclude, to determine the wavelength of a radio wave, you take the speed and divide it by the frequency.
Typical radio wave frequencies are about
88
~
108
MHz
. The wavelength is thus typically about
3.41
×
10
9
~
2.78
×
10
9
nm
.
