Answer:
Minimum required frequency is υmin = 654.9 x 10¹² Hz
Explanation:
The energy of a photon is given by the equation:
E = hυ
where,
E = energy of photon
h = Plank's Constant = 6.626 x 10⁻³⁴ J.s
υ = frequency
The minimum energy of photon, must be equal to the work function of Calcium.
Emin = ∅₀ = h(υmin)
υmin = ∅₀/h
where,
υmin = minimum frequency
∅₀ = work function = 4.34 x 10⁻¹⁹ J
Therefore,
υmin = 4.34 x 10⁻¹⁹ J/6.625 x 10⁻³⁴ J.s
υmin = 654.9 x 10¹² Hz
