<span>Answer:
skater x km/h
cyclist 20 faster x + 20 km/h
skater 30 km
cyclist 80 km
skater time = cyclist time
t=d/r
30 / x = 80 /( x + 20
cross multiply
30 ( x + 20 ) = 80 x
30 x + 600 = 80 x
30 x - 80 x = -600
-50 x = -600
/ -50
x = 12 km/h
12 km/h skater</span>
<h2>Answer: protons and neutrons.
</h2>
The atomic nuclei of almost all elements consist of protons and neutrons.
The nucleus of an atom has very small dimensions. However, it <u>occupies its central part and concentrates more than 99% of its total mass.
</u>
It is in the nucleus that the protons (positive charge) and neutrons (neutral charge) are found.
Answer:
Distance: 1600 m Displacement: 0
Explanation:
The distance is because He ran 400 meters 4 times getting 1600 m
4*400=1600
The displacement is 0 because displacement is the total distnce away from the starting point and since he ran laps around the track in the end he ended up in the same spot as last time.
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
.
