The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » sci.math.* » sci.math

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: How precisely can a right angle be measured?
Replies: 6   Last Post: Apr 6, 2013 2:47 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Tom Potter

Posts: 497
Registered: 8/9/06
Re: How precisely can a right angle be measured?
Posted: Apr 3, 2013 6:59 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"Will Janoschka" <> wrote in message
> On Tue, 2 Apr 2013 14:27:30, "Tom Potter" <> wrote:

>> "Will Janoschka" <> wrote in message

>> > On Tue, 2 Apr 2013 09:07:58, "Tom Potter" <> wrote:
>> >

>> >> How would one measure a right angle
>> >> without using geometry,
>> >> or the 3-4-5 relationship,
>> >>
>> >> and how precisely can a right angle be measured?
>> >>

>> > Optically to about an eighth wavelength, for all
>> > three right angles of a corner cube.
>> > Is that close enough for government work?

>> What are the optics based on?
>> A measurement, a theory or on geometry?

> A measurement. A corner cube, 3 orttogonal
> right angle reflectors, reflects light to its orign over
> wide angles and reverses parity, Optically, any
> deviation off any angle results in multiple images.
> The onesleft on our moon were good to 1/4th
> wave visable They have distorted some over time.

How do they measure the right angle,
what do they use as the right angle reference,
and what units are the deviations from a right angle in?

Tom Potter

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.