The Photelectric effect (1 Viewer)

[ausm8]

Hi, I have a few questions about the Photoelectric effect.

) If Max Kinetic energy is graphed against frequency of incident light, what does the gradient represent?

2) What does a negative stoppping potential mean?

Cheers

 

[Riviet]

1) Remembering the equation E=hf, we arrange this equation to obtain h=E/f, where the gradient e/f represents Plank's constant.

2) The negative stopping potential is the potential (or voltage) required to reduce the current to zero, in which the electrons with the maximum kinetic energy are stopped.

 

[ausm8]

Sorry, I think i may have not phrased the question properly.

What is the difference between a negative and positive stopping voltage eg:
-1 x 10^-1 and 1 x 10^-1.

Also, if you multiply a negative stopping voltage, by q, the Max kinetic energy is found. But is this answer positive or negative?

Cheers