quantization of energy

. What will happen to a photon as result of decreasing its wavelength?

• Its energy will increase

• Its energy will decrease

• ts energy will not be affected

• Its frequency will decrease

Which of the statements below is true for the emission spectra

• The emission is only in the visible region

• The peak intensity increases with temperature

• The peak intensity decreases with temperature

• The peak frequency decreases with temperature

• The peak wavelength increases with temperature

An object emits 10¹² photon at a frequency of 2.5 x 10¹⁹ Hz How much is the total energy it emits?

• 2.5 x 10¹⁹ J

• 2.5 x 10^{19 eV}

• 0.17 J

• 0.17 eV

A black body in thermal equilibrium emits electromagnetic radiation. Which of the statements below are correct?

• The radiation has a specific spectrum and intensity

  that depends only on the temperature of the body

• Max Planck described the radiation by assuming that

  the electromagnetic radiation was emitted in discrete energies

• A black body is an idealized object which emits all

  frequencies

Five emission spectra for five identical objects are shown in the figure below. the higest temp is for graph________________ and the object that has peak at lowest energy is _________

• A and B

• A and F

• B and F

• C and B

The radiation emitted by blackbody X peaks at longer wavelength than that of blackbody Y.

the temperature of blackbody X greater than blackbody Y?

• true

• false

find the surface temperature of a star, given that the blackbody radiation peak occurs at a frequency of 1.25 x 10¹⁵ Hz

• 21300K

• 12500K

• 213K

• 125K

A photon has a frequency of 4,3 x 10¹⁴ Hz, the energy of this photon is ___________ _J and the wavelength is ______nm

• 2.8 x 10^-19 and 7 x 10^-7

• 2.8 and 700

• 2.8 x 10^-19 and 700

• 2.8 and 7

when emission intensity of the object’s

temperature increased The intensity will increase too

• true

• fasle

The diagram shows the predicted and observed spectra of a black body radiation. the graph matches only at lower frequency

• true

• false