Question

Calculate the mass of a photon with wave length 3.6 A

Answer 1

λ = h / MV
M = h / λV
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M --- mass of proton
h --- planck's constant
λ --- Wave length
V --- Velocity
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λ = 3.6 A⁰ = 3.6 × 10⁻¹⁰ m
h = 6.626 × 10 ⁻³⁴
V = 3 × 10⁸ m/s
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∴ M = ( 6.626 × 10 ⁻³⁴ ) / [ ( 3.6 × 10⁻¹⁰ ) × ( 3 × 10⁸)]

= 6. 135 × 10⁻³³ kg //