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In a photoelectric experiment, the wavelength of the light incident on a metal is changed from 300 nm to 400 nm. The decrease in the stopping potential is close to: ( e hc = 1240 nm–V)

1. 0.5 V
2. 1.0 V
3. 2.0 V
4. 1.5 V

Correct answer: 1.0 V

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