**A production line inspector wants a mirror that produces an upright image within magnification of 7.9 when it is located 10.0 mm from a machine part.**

What is its radius of curvature?

What is its radius of curvature?

**I used:**

r/2 = f

1/f=(1/do) + or - (1/di)

m=di/do

r/2 = f

1/f=(1/do) + or - (1/di)

m=di/do

**first i did 7.9=10/do**

then i found that do=1.27mm

So then i did 1/f=1/1.27+1/10

I got f=1.3

Then i multiplied that by 2

(r/2)=f

So then i got 2.6

I tried -2.6 for the heck of it

and then i did it all again except i did:

1/f=1/1.27-1/10

and calculated it all out and it was still wrong.

Even when it was negative.

Argh. Help? =( Because i have 2 more like this. x.x

then i found that do=1.27mm

So then i did 1/f=1/1.27+1/10

I got f=1.3

Then i multiplied that by 2

(r/2)=f

So then i got 2.6

I tried -2.6 for the heck of it

and then i did it all again except i did:

1/f=1/1.27-1/10

and calculated it all out and it was still wrong.

Even when it was negative.

Argh. Help? =( Because i have 2 more like this. x.x