Question

A current is detected in a photoelectric-effect experiment when the cathode is illuminated with green light.

Part A

Will a current necessarily be detected if the cathode is illuminated with blue light? Select the correct answer and explanation.

(1)Photons of blue light have less energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there could be no current with blue light.

(2)Photons of blue light have less energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there will also be a current with blue light.

(3)Photons of blue light have more energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there could be no current with blue light.

(4)Photons of blue light have more energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there will also be a current with blue light.

Part B

Will a current necessarily be detected if the cathode is illuminated with red light? Select the correct answer and explanation.

(1)Photons of red light have less energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there could be no current with red light.

(2)Photons of red light have less energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there will also be a current with red light.

(3)Photons of red light have more energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there could be no current with red light.

(4)Photons of red light have more energy than photons of green light. Therefore, if there is a current in a photoelectric-effect apparatus with green light, then there will also be a current with red light.

Answer 1

A

Option 4 is correct , because photon of blue light has more energy then photon of green light. Blue light has capabilities to produce Larger as compare to current produced by green light . According to the (VIBGYOR ) , Voilet has greater energy then indigo , ......................, Red) . SO, by this (VIBGYOR ) blue has greater energy then green. Due to higher energy of blue option 4 is correct.

B

1) Option 1 is correct because photon of red light has less energy than photons of green light. if there is a current due to green llight than there could be no current with red light.