Dual Nature of Radiation and Matter

Q1.The minimum energy required for an electron to escape from the surface of a metal is called:

• AKinetic energy
• BThreshold energy
• CWork function
• DIonisation energy

Q2.A metal has work function 4.2 eV. Will it show photoelectric emission for incident radiation of wavelength 330 nm? (h = 6.63×10⁻³⁴ J·s, c = 3×10⁸ m/s)

• AYes, with Kmax = 0.18 eV
• BNo, the photon energy is less than the work function
• CYes, with Kmax = 1.2 eV
• DYes, with Kmax = 3.76 eV

Q3.The stopping potential is independent of the intensity of incident light but depends on:

• AOnly the intensity
• BThe frequency of incident light and the nature of the emitter
• COnly the wavelength of light
• DThe number of photons

Q4.An electron is moving with a speed of 5.4 × 10⁶ m/s. What is its de Broglie wavelength? (m_e = 9.11×10⁻³¹ kg, h = 6.63×10⁻³⁴ J·s)

• A0.135 nm
• B1.35 nm
• C0.0135 nm
• D13.5 nm

Q5.The energy of a photon of frequency ν is:

• AE = hν²
• BE = h/ν
• CE = hν
• DE = hc