Quantum theory of light and photoelectric effect

24 questions on Quantum theory of light and photoelectric effect from the Atomic Structure chapter: 4 NEET level, 10 JEE Main, 10 JEE Advanced. Each one opens with its answer and solution.

• Among the following radiations, the photon of which has the highest energy? NEET level
• When the frequency of the incident light is below the threshold frequency of a metal, increasing the intensity of the light NEET level
• The wavelength of radiation of frequency 1.5x10^15 Hz is (use c = 3.0x10^8 m s^-1) NEET level
• Light of photon energy 3.5 eV falls on a metal of work function 2.0 eV. The maximum kinetic energy of the emitted electrons is NEET level
• The energy of a photon of wavelength 620 nm is closest to (use h=6.626x10^-34 J s, c=3.0x10^8 m s^-1, 1 eV=1.6x10^-19 J) JEE Main level
• Light of frequency 2nu_0 (nu_0 = threshold frequency) ejects photoelectrons of maximum kinetic energy K_1. When the frequency is raised to 4nu_0 on the same met... JEE Main level
• A monochromatic beam of constant power and wavelength 600 nm gives a saturation photocurrent I_1 on a metal. The wavelength is changed to 400 nm at the same pow... JEE Main level
• The energy of one mole of photons of wavelength 500 nm is closest to (use h=6.626x10^-34 J s, c=3.0x10^8 m s^-1, N_A=6.022x10^23 mol^-1) JEE Main level
• The work function of a metal is 2.3 eV. Find the threshold wavelength in nm, to the nearest integer. Use h=6.626x10^-34 J s, c=3.0x10^8 m s^-1, 1 eV=1.6x10^-19 ... JEE Main level
• Ultraviolet light of wavelength 260 nm falls on a metal of work function 2.1 eV. Find the maximum kinetic energy of the photoelectrons in eV, to two decimals. U... JEE Main level
• A lamp radiates 30 W entirely as monochromatic light of wavelength 550 nm. Find the number of photons emitted per second, in units of 10^19, to two decimals. Us... JEE Main level
• Light of frequency 9.2x10^14 Hz falls on a metal of work function 2.4 eV. Find the stopping potential in volts, to two decimals. Use h=6.626x10^-34 J s and 1 eV... JEE Main level
• For photoelectric emission from a metal, which statements are correct when the light frequency is above the threshold frequency? JEE Main level
• Light of wavelength 330 nm is incident separately on four metals P, Q, R and S whose work functions are 2.2, 3.6, 4.2 and 3.9 eV respectively. Use h=6.626x10^-3... JEE Main level
• For a certain metal the stopping potential for light of wavelength 300 nm is exactly 3 times that for light of wavelength 500 nm. The work function of the metal... JEE Advanced level
• A monochromatic source delivers 2.0 mW of light of wavelength 400 nm to a photocell. Only 0.50% of the incident photons eject an electron, and every ejected ele... JEE Advanced level
• An isolated, initially neutral metal sphere of radius 5.0 cm and work function 2.0 eV is illuminated by light of wavelength 250 nm. Photoelectrons leave until t... JEE Advanced level
• Light of wavelength 200 nm falls on a metal of work function 4.2 eV. The fastest photoelectrons enter a uniform magnetic field of 1.0 mT perpendicular to their ... JEE Advanced level
• In a photoelectric experiment the stopping potentials measured are 0.49 V for light of frequency 6.0x10^14 Hz and 1.73 V for 9.0x10^14 Hz. The threshold frequen... JEE Advanced level
• Sunlight of mean wavelength 550 nm and intensity 1.5 kW m^-2 falls normally on a surface of area 1.0 cm^2. Find the number of photons arriving per second in uni... JEE Advanced level
• When light of wavelength 200 nm falls on a metal, the maximum kinetic energy of the photoelectrons is 2 times that obtained with light of wavelength 300 nm. Fin... JEE Advanced level
• A metal has threshold wavelength 280 nm. Light of wavelength 180 nm falls on it. Find the speed of the fastest photoelectrons in units of 10^5 m s^-1, to one de... JEE Advanced level
• Light of wavelength 365 nm is incident on metals A and B of work functions 2.0 eV and 3.0 eV. Use h=6.626x10^-34 J s, c=3.0x10^8 m s^-1, 1 eV=1.6x10^-19 J. Sele... JEE Advanced level
• A metal surface emits photoelectrons under monochromatic light. The incident power is kept constant, but the frequency is raised (still above threshold). Assumi... JEE Advanced level