<u>Given:</u>
Frequency (ν) = 319 THz
<u>To determine:</u>
The wavelength corresponding to the given frequency
<u>Explanation:</u>
Wavelength (λ) and Frequency(ν) are related as:
λ = c/ν
where c = speed of light = 3*10⁸ m/s
Now:
SI unit of frequency is Hertz (Hz) also expressed as cycles per second
i.e 1 Hz = 1 s⁻¹
1 Terahertz (THz) = 10¹² Hz
therefore the given frequency ν = 319 *10¹² s⁻¹
λ = 3 * 10⁸ ms⁻¹/319 *10¹² s⁻¹ = 940 * 10⁻⁹ m
since 1 nanometer (nm) = 10⁻⁹ m
The wavelength is λ = 940 nm
Ans: The infrared wavelength = 940 nm
Density is an intrinsic property, so it is independent of the amount of substance present: one gold coin would have the same density as a solid gold boulder.
So if the density of gold is 19.3 g/cm³, the density of a bar of gold and the pieces into which the bar is cut would all be 19.3 g/cm³.
A compressed spring is the right answer
<span>Dark matter has been given this name because it doesn’t seem to interact with regular matter in any way. It doesn’t collide with it, or absorb energy from it. We can’t see it or detect it with any of our instruments. We only know it’s there because we can see the effect of its gravity.</span>