Quantum Mechanics

Which of the following is the characteristic of a black body?

• A perfect absorber but an imperfect radiator

• A perfect radiator but an imperfect absorber

• A perfect radiator and a perfect absorber

• A perfect conductor

What is Compton shift?

• Shift in frequency

• Shift in charges

• Shift in radiation

• Shift in wavelength

Compton shift depends on which of the following?

• Incident radiation

• Nature of scattering substance

• Angle of scattering

• Amplitude of frequency

As the wavelength of the radiation decreases, the intensity of the black body radiations ____________

• Increases

• Decreases

• First increases then decrease

• First decreases then increase

During Einstein’s Photoelectric Experiment, what changes are observed when the frequency of the incident radiation is increased?

• The value of saturation current increases

• No effect

• The value of stopping potential increases

• The value of stopping potential decreases

What is the time lag between the incidence of photons and the ejection of photoelectrons?

• Greater than 10^-5 s

• Between 10^-5 s and 10^-9 s

• Less than 10^-9 s

• 1 second

How does the intensity affect the photoelectric current?

• As intensity increases, the photoelectric effect increases

• As the intensity increases, the photoelectric effect decreases

• As the intensity decreases, the photoelectric effect becomes twice

• No effect

The photoelectric emission could be explained by the ____________

• Wave nature of light

• Particle nature of light

• Dual nature of light

• Quantum nature

The work function of lithium is 2.5 eV. The maximum wavelength of light that can cause the photoelectric effect in lithium is ______________

• 3980 Å

• 4980 Å

• 5980 Å

• 6980 Å

The Kinetic energy of a photoelectron emitted on shining a light of wavelength 6.2 X 10-6 m on a metal surface of work function 0.1 eV is _________________

• 0.01 eV

• 0.02 eV

• 0.1 eV

• 1 eV