Find the photon energy in units of electron volts of electromagnetic waves of wavelength 40 m ?

Question

Find the photon energy in units of electron volts of electromagnetic waves of wavelength 40 m ? (A) 3 × 10-8 eV (B) 3.1 × 10-8 eV (C) 3.2 × 10-8 eV (D) 3.3 × 10-8 eV

Tardigrade Admin · Accepted Answer

E =( hc /λ)=(6.6 × 10-34 × 3 × 108/40) J E =(6.6 × 10-34 × 3 × 108/40 × 1.6 × 10-19) eV =(19.8 × 10-7/64) =0.30 × 10-7 eV E=3.1 × 10-8 eV

Q. Find the photon energy in units of electron volts of electromagnetic waves of wavelength $40 m ?$

$3 \times 1 0^{- 8} e V$

$3.1 \times 1 0^{- 8} e V$

$3.2 \times 1 0^{- 8} e V$

$3.3 \times 1 0^{- 8} e V$

$E = \frac{h c}{λ} = \frac{6.6 \times 1 0 ^{- 34} \times 3 \times 1 0 ^{8}}{40} J$
$E = \frac{6.6 \times 1 0 ^{- 34} \times 3 \times 1 0 ^{8}}{40 \times 1.6 \times 1 0 ^{- 19}} e V$
$= \frac{19.8 \times 1 0 ^{- 7}}{64}$
$= 0.30 \times 1 0^{- 7} e V$
$E = 3.1 \times 1 0^{- 8} e V$

Q. Find the photon energy in units of electron volts of electromagnetic waves of wavelength 40m?

3×10−8eV

3.1×10−8eV

3.2×10−8eV

3.3×10−8eV