Quantum physics

Photoelectrons will be ejected from a material surface if?

• The threshold frequency is greater than the photon frequency

• The work function is less than the photon energy

• The intensity of light is high enough

• The wavelength of photon is maximum

A monochromatic light beam with a quantum energy of 9.0 eV is incident upon a photocell. The work function of the photocell is 4.1 eV. What is the maximum kinetic energy of the electron.

• 4.2 eV

• 4.4 eV

• 4.7 eV

• 4.9 eV

The SI unit of frequency is the __________.

• meter

• second

• hertz

• meter per second

True or False? The wavelength and frequency of all waves are inversely proportional to each other.

• True

• False

Which of the following colors of visible light has the highest frequency?

• Blue

• Green

• Orange

• Red

• Violet

Which of the following colors of visible light has the lowest frequency?

• blue

• green

• yellow

• red

• violet

The photoelectric effect only occurs if the light shining on the metal is:

• coherent.
• above a minimum intensity.
• above a minimum frequency.
• above a minimum wavelength.

Wave -particle duality is supported by...

• electrons behaving as particles with ordinary matter

• electrons behaving as waves when travelling through space

• the photo electric effect

• all of the above

Planck's constant can be found ...

• energy of a particle x speed of light / wavelength

• energy of a particle x speed of light / frequency of light

• energy of a particle x wavelength / speed of light

• slope of the cut-off voltage vs frequency graph

De Broglie equation

• relates the momentum of a mass to its wavelength

• relates the energy of a mass to its wavelength

• relates the frequency of a mass to its wavelength

• relates the work function of a mass to its wavelength