An electron and a photon have same wavelength of $10^{-9} \,m$. If $E$ is the energy of the photon and $p$ is the momentum of the electron, then the magnitude of $E / p$ (in $SI$ unit) is
An electron and a photon have same wavelength of $10^{-9} \,m$. If $E$ is the energy of the photon and $p$ is the momentum of the electron, then the magnitude of $E / p$ (in $SI$ unit) is
- [KVPY 2016]
- A
$1.00 \times 10^{-9}$
- B
$1.50 \times 10^8$
- C
$3.00 \times 10^8$
- D
$1.20 \times 10^7$
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