Thursday
May 5, 2016

# Homework Help: Physics/Engineering

Posted by Z32 on Thursday, November 17, 2011 at 7:26pm.

1. The problem statement, all variables and given/known data

I am using a Vishay strain indicator with it hooked up to a strain gage hooked up 1" away from the wall on the solid beam. The beam is .5" by .5", and it is solid. The beam is 16" long and I am putting weights at the end of the beam. The weights are 1, 2, 5, 10, 15, and 20 lbs. On each weight, I recorded a strain(uin/in). It states to use the modulus of elasticity E_aluminum 10x10^6 to convert to psi. My question is how do I calculate the M part for the bending stress?

2. Relevant equations

bending stress = MC/I

modulus of elasticity E_aluminum 10x10^6 to convert to psi.

3. The attempt at a solution

For C, .5/2= .25

For I, (1/12)*b*h^3 or (1/12)*.5*.5^3 = .0052083

How do I find my M?

For 1 lb, would it be M-1lb(16")=0 or M=16 lb.in but I don't get it why it says to use E_aluminum = 10x10^6 psi to convert.