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The threshold frequencies of caesium and potassium metals are given in the table
below.
11.1 Define the term work function in words. (2)
11.2 Which ONE of the two metals in the table has the higher work function?
Give a reason for the answer by referring to the information in the table. (2)
The simplified diagrams below show two circuits, A and B, containing photocells.
The photocell in circuit A contains a caesium metal plate, while the photocell in
circuit B contains a potassium metal plate.
Ultraviolet light with the same intensity and wavelength of 5,5 x 10-7 m is incident on
the metal plate in EACH of the photocells and the ammeter in circuit A registers a
current.
11.3 By means of a calculation, determine whether the ammeter in circuit B will
also register a current. (3)
11.4 Calculate the maximum kinetic energy of an ejected electron in circuit A. (5)
11.5 How will the maximum kinetic energy of the ejected electron, calculated in
QUESTION 11.4, change when the intensity of the incident light increases?
Choose from: INCREASES, DECREASES or REMAINS THE SAME. (1)
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TOTAL: 150