Q5 · 2023 · Paper 2Simple familiar4 marks
QUESTION 5 (4 marks)
Describe what happens when light is shone onto a metallic surface in the context of the photoelectric effect.
WORKED SOLUTION
4 marksQCAA guide · typeset solution
ANSWER
See worked solution below.
Worked solution
Sample response The
Light with energy equivalent to Af has the ability to produce id
photoelectrons from a metallic surface. hf
When the frequency of light is below the threshold frequency for « de
the metallic surface, the light will be reflected with no transfer of lig
energy. .
When the frequency of light is above the threshold frequency for -
the metallic surface, the energy of the photons will be absorbed eid
and photoelectrons with kinetic energy proportional to the excess in
energy will be released. i]
The intensity of incident light is proportional to the number of
photoelectrons for frequencies greater than the threshold
frequency.
he response:
e identifies incident light has energy equivalent to
hf [1 mark]
• describes transfer of energy when frequency of
light is
— below the threshold frequency [1 mark]
— above the threshold frequency [1 mark]
e identifies relationship between intensity of
incident light and resultant photoelectrons
[1 mark]
One QCAA sample method typeset for web; criterion wording is adapted from the official marking guide.
How many marks did you earn?
Compare your working with the guide above.