Who was first: science or scientist? Bonus: RADAR explained in 9.99 seconds

The word science comes from the Latin scientia, meaning knowledge, and was introduced in English language in the 1300s, however the people who were doing science were called natural philosophers. Only around 1830 Whiliam Whewell coined the term scientist.

And now about RADAR: RAdio Detection And Ranging, works by broadcasting radio waves and then detecting reflections coming from the objects.
Distance = 1/2 time * speed of light.
How fast is moving relative to us: speed = cz ( in video speed= 0.01m * z ) – z is frequency shift, c speed of light, – using Doppler Shift (also see Doppler Effect on Wiki)

Frequency shift (z) calculations with lambda being the wavelength:
1+z =lambda(observed) / lambda(emitted).

Example: if a star is moving away from us and the frequency for Ca II is 397, instead of 393, as we know it, then the frequency shift will be:
1+z= 397/393 = 1,01, with z = 0.01.

The same for objects detected with RADAR, but the frequency shift is way smaller.

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