# Homework Help: Optics problem

1. Aug 15, 2009

### jsalapide

two plane mirrors facing each other are 10m apart. A woman stands 3 m from one of the mirrors and looks at the mirror and sees two distinct images. How far are these images from the woman?

this one is a bit confusing.. can somebody knows how to solve it?

2. Aug 15, 2009

### alex_rodin

Draw the mirrors and imaginary images S1' and S2' of the women in each of the mirrors. Also draw an imaginary image of the imaginary image in the other mirror. So you can calculate the distances between the woman and the imaginary imaginary images.

3. Aug 15, 2009

### jsalapide

I followed what you said..

should the answer be 16 m??

4. Aug 15, 2009

### alex_rodin

No. The answer is 6m and 14m for first and second images.

5. Aug 15, 2009

### jsalapide

ok, the first image was 6m. but how do you get 14m for the second image?

I assume that the distance of the second image is 14 m if the woman is facing at the mirror 7m away from her. But what if she is facing the mirror which is 3m away from her? could the second image still be 14m?

6. Aug 15, 2009

### alex_rodin

You are right. The second distance is 20m = (14m + 3m) + 3m.

7. Aug 15, 2009

### jsalapide

ok sir, thanks for the time..