The energy of a photon is given by
E = h × v
where:
E is the energy in joules/photon
'h' is the constant 6.63 × 10⁻³⁴
'v' is the frequency 7.55 × 10¹⁴
Substitute 'h' and 'v' into the formula we have
E = (6.63×10⁻³⁴) × (7.55×10¹⁴)
E = (6.63×7.55) × (10⁻³⁴ × 10¹⁴)
E = 50.0565 × 10⁽⁻³⁴⁺¹⁴⁾
E = 50 × 10⁻²⁰ joules/photon