Which of the following statements are correct, if the threshold frequency of caesium is 5.16×1014 Hz ?
A. When Cs is placed inside a vacuum chamber with an ammeter connected to it and yellow light is focused on Cs the ammeter shows the presence of current.
B. When the brightness of the yellow light is dimmed, the value of the current in the ammeter is reduced.
C. When a red light is used instead to the yellow light, the current produced is higher with respect to the yellow light.
D. When a blue light is used, the ammeter shows the formation of current.
E. When a white light is used, the ammeter shows formation of current.
Choose the correct answer from the options given below :
Held on 7 Apr 2025 · Verified 6 Jul 2026.
A, D and E Only
B, C and D Only
A, C, D and E Only
A, B, D and E Only
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