Which equation was used by albert einstein to explain the photoelectric effect? [e = energy, h = planck’s constant, and v = frequency.] e = h/v e = hv e = v/h e = h - v

 
E = hv
where
E = energy,
h = Planck's constant
v = frequency.

Explanation:
Einstein proposed that electromagnetic energy was transmitted in quanta or packets. This gave rise to modern Quantum Physics.
The usual representation of a photon or energy packet is
E = hf
where f =  frequency.
The frequency is related to the speed of light by
c = fλ
where
c = speed of light
λ = wavelength

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