The work function for a metal is 1.8eV. Light of 5000Å is incident on it. Calculate (a) threshold frequency and threshold wavelength, (b) maximum kinetic energy of the emitted electrons, (c) maximum velocity of the emitted electrons, (d) if the intensity of the incident light be doubled, then what will be the maximum kinetic energy of the emitted electrons? given, `h=6.63xx10^(-34)Js, m_e=9xx10^(-31)kg, c=3xx10^8ms^-1.`

Explanation

To solve the given problem step by step, we will break it down into parts as per the questions asked.

### Given Data:
- Work function (φ) = 1.8 eV
- Wavelength of light (λ) = 5000 Å = \(5000 \times 10^{-10}\) m
- Planck's constant (h) = \(6.63 \times 10^{-34}\) Js
- Speed of light (c) = \(3 \times 10^{8}\) m/s
- Conversion factor: \(1 \text{ eV} = 1.6 \times 10^{-19} \text{ J}\)
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