The figure below shows a set up that was used to demonstrate the photoelectric effect. i)If the electroscope was negatively charged, State the observation made. ii) Explain...

The figure below shows a set up that was used to demonstrate the photoelectric effect.

i)If the electroscope was negatively charged, State the observation made.
ii) Explain your answer in (i) above.
iii) State and explain what would happen if the electroscope was positively charged.

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i) The leaf falls. OR The leaf divergence decreases.
ii) Photoelectrons are emitted from the zinc plate which is negatively charged. The photoelectrons are then repelled by the negative charges on the plate and the electroscope becomes discharged.
iii) The leaf divergence remains unchanged. The photoelectrons emitted do not escape due to attraction by the positive charges on the plate.

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Kavungya answered the question on October 30, 2019 at 13:18

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