<span> is the volume of fluid which passes per unit time; usually represented by the symbol Q (sometimes V̇).</span>
Answer:

Explanation:
Given that,
An infrared telescope is tuned to detect infrared radiation with a frequency of 4.39 THz.
We know that,
1 THz = 10¹² Hz
So,
f = 4.39 × 10¹² Hz
We need to find the wavelength of the infrared radiation.
We know that,

So, the wavelength of the infrared radiation is
.
Answer:
define 1 second time
One second is the time that elapses during 9,192,631,770 (9.192631770 x 10 9 ) cycles of the radiation produced by the transition between two levels of the cesium 133 atom. ... One second is equal to 1/86,400 of a mean solar day.
Explanation:
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