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barry_scott
Nov1-09, 05:21 PM
Hi guys, i'm new to the physics world and am getting a bit confused with some of the terms used, stopping me getting the maths i need. Essentially I need to measure the deflection at the end of a beam, supported at one end. Like this:

http://upload.wikimedia.org/wikipedia/commons/e/e9/Cantilever_Beam.svg

I will have the beam at different angles with different weights on the end and different gravity. So essentially what i need is a formula where i can specify:


Gravity
Beam Angle
Beam length
Beam end weight


and obtain a deflection. I'm guessing i will initially have to measure the deflection to obtain information on the strength of the material. Then use this value to calculate future deflections based on weight.

Thanks for any input you guys might have!

willem2
Nov1-09, 06:05 PM
Whats wrong with the Deflection_(engineering) article in wikipedia?

barry_scott
Nov7-09, 03:25 PM
http://users.aber.ac.uk/mrb6/deflection.gif

The deflection article on wikipedia provides a formula for the calculation of a deflection, this deflection is given as a single value. e.g. 10.6mm
I'm assuming this value is for the vertical deflection of the beam? (labeled Dy)
In which case i also need to calculate the horizontal deflection of the beam (labeled Dx). Essentially shortening of the beams span due to its bending.

or is it the total deflection of the beams end point? (labeled tD)
in which case i need to find the direction this deflection is in (Da), to then calculate the horizontal and vertical deflections.

I would be very grateful for any help in finding a solution to this. Thanks.