Re: Double concave mirror toy

[Robert Cohen <Robert.Cohen@PO-BOX.ESU.EDU>]

> -----Original Message-----
> From: kowalskil [mailto:kowalskil@MAIL.MONTCLAIR.EDU]
> Sent: Tuesday, May 07, 2002 8:06 PM
>
> [snip]
>
> I have no classes today but came to school to observe what
> I think is impossible. I was going to create a sharp image of
> the frosted light bulb on the paper screen, remove the screen
> and send the laser pointer beam through the area where the
> real image (no longer visible) is located. Before investing
> any time let me ask you this question. Do you think the light
> from my laser pointer will be partially reflected in the area
> of the real image? I do not think this to be possible but I
> met you last year and I know that you are serious. Therefore
> I will set up the optical bench as soon as I hear from you.

You won't see any laser light on the image if you cannot see the image in
the first place.  You must first position yourself in a way that you can see
the image.  Rather than remove the screen, just lower it so that the image
is just above it.  Then look into the lens (with the screen between you and
the lens) so you can see the image (now "floating" above the screen).  Take
a laser and point it at the image.  It should produce a dot of light on the
image.  Why shouldn't it?

____________________________________________
Robert Cohen; rcohen@po-box.esu.edu; http://www.esu.edu/~bbq
Physics, East Stroudsburg Univ., E. Stroudsburg, PA 18301