# Homework Help: Photoelectric Effect, Threshold Frequency etc.

1. Oct 2, 2007

### Andresx90

1. The problem statement, all variables and given/known data
Light of intensity 1.5 x 10 (x)-2 Wm/2 and wavelength 250 x 10 (x)-9m is incident on an iron surface of area 1 x 10 (x) -4 m2. The iron surface reflects 95% of the light. The threshold frequency for iron is 1.1 x 10x15 Hz.
Calculate:
1) The intensity of light available for the photoelectric effect
2) The number of electrons emitted per second
3) The work function in electron volts for iron
4) The stopping potential for this radiation

Could someone answer this question for me showing working used as well.

(x) in this instance means to the power of.

2. Relevant equations

3. The attempt at a solution

1) 95% of the light intensity already given (no calculator)

2. Oct 2, 2007

### Kurdt

Staff Emeritus
We will not answer the questions for you here at PF. We can help guide you to the answer but most of the work has to be your own. Please refer to the forum guidelines.