Question

the mass of the proton if the wavelength is 4.2 angstroms​

Answer 1

Answer:

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