Answer: D. A wave with a shorter wavelength is always faster than one with a longer wavelength
Explanation: "Imagine two sets of waves that have the same speed. <u><em>If one set has a longer wavelength, it will have a lower frequency (more time between waves). If the other set has a shorter wavelength, it will have a higher frequency</em></u> (less time between waves). Light moves even faster AND has shorter wavelengths."
Why it's not C: "The number of complete wavelengths in a given unit of time is called frequency (f). <em><u>As a wavelength increases in size, its frequency and energy (E) decrease</u></em>. From these equations you may realize that as the frequency increases, the wavelength gets shorter. As the frequency decreases, the wavelength gets longer."
Why it's not B: "The frequency does not change as the sound wave moves from one medium to another. Since the speed changes and the frequency does not, the wavelength must change."
Why it's not A: "Do loud sounds travel faster than soft sounds? No. Both travel at the same speed The speed depends on the medium it passes through. Louder sounds are simply sound waves with higher amplitude traveling at the same speed."
The two different isotopes have weights :
w1 = 78.918 amu
w2 = 80.916 amu
average weight w3 = 79.903 amu
The mixing of two components can be modeled as
let the fraction of w1 be 'x'
hence 
now this is a linear equation in 'x'. Substituting the values we get
x = 0.507
hence the percentage of Br79 = 50.7% and the percentage of BR81 = 49.3%
Answer:
The wavelength of the sound waves are, λ = 26.92 m
Explanation:
Given data,
The frequency of the sound waves, f = 13 Hz
The speed of sound waves in air, v = 350 m/s
The velocity of the wave in the medium is equal to the product of its wavelength and its frequency.
The formula for the wavelength of the waves is,
λ = v / f
Substituting the given values in the above equations,
λ = 350 m/s / 13 Hz
= 26.92 m
Hence, the wavelength of the sound waves are, λ = 26.92 m
A. Relaxing under a tree.
The parasympathetic nervous system is known as the “rest and digest” system. Activities that require as little movement as possible help the heart rate to slow down. The other activities would be associated with the Sympathetic nervous system which is known as the “fight or flight,” or when your heart rate is up and running.
