Answer:
1) Seven tectonic plates can be identified in the earth today.
2) The old sea floor sinks back into the earth to be recycled at the subduction zone.
3) The world's last supercontinent is known as Pangaea.
4) Pangaea began breaking up approximately 175 million years ago.
Explanation:
I hope this helped!!!!
A)
amplitudes
B)
wave speeds
C)
wavelengths
D)
polarization
Different colors after reflection appear due to the different wavelengths of light. Therefore, option C is correct.
The wavelength of the light can be defined as the distance between the two points in phase w.r.t. each other such as two crests or troughs on a wave. The frequency of the light is the number of oscillations of a wave in one second and has S.I. units of per second or hertz.
The expression between frequency (ν), wavelength (λ), and speed of light (c) is:
c = νλ
A wave moving at a fixed wave speed has a wavelength that is inversely proportional to the frequency therefore, the waves with higher frequencies have shorter wavelengths, while lower frequencies have higher wavelengths.
The speed depends upon the medium as it propagates. In particular, the speed of light in a particular medium is less than in a vacuum, therefore the same frequency will have a shorter wavelength.
When the light is reflected the colors are formed as due to different wavelengths.
Learn more about wavelength and frequency, here:
#SPJ6
Answer : The correct option is, (D) They have the same number of electrons in their outermost shells.
Explanation :
Periods : A row in the periodic table is known as periods.
The common features about the elements of a period are :
Each periods has elements with the same number of electron shells or energy levels or shell.
They transition from metal to noble gas that means they move from metal to non-metal and then non-metal to noble gas.
Groups : A column in the periodic table is known as groups.
The common features about the atoms of elements in a same group are :
Each groups has elements with the same number of valance electrons or have same of electrons in their outermost shells.
The elements in the same group have similar chemical properties.
The elements in the same group have similar physical properties.
Hence, the correct option is, (D) They have the same number of electrons in their outermost shells.
Sound waves
Earthquake waves
All of these have which characteristic in common?
Answer:
They all have the characteristic "energy" in common
Explanation:
Energy is power derived from the utilization of physical or chemical resources, especially to provide light / heat or to work machines. X-rays, UV Light Waves, Sound Waves, and Earthquake Waves all have energy.