Feb 26, 2016

Feb 26, 2016

Feb 26, 2016

# Laboratory Investigation of Hooke’s Law

/ On: May 08, 2017 /

## Apparatus:

UTM , test specimen, divider, vernier caliper, scale.

## Procedure:

1. Prepare the test specimen that is steel bar and find its diameter at tree different places and find its man value.

2. Mark two points 8" a part of 2 ft long steel bar.

3. Insert the bar in jaws for gripping the steel bar and select suitable bar on UTM. Place the steel bar and fix it.

4. Start t machine and start applying load.

5. There will be gradual increase in length which will be directly proportional to applied load.

6. During this load application measure change in length at different load, till the steel bar breaks.

7. Find the stress and strain at those points and investigate the law by drawing the graph between stress and strain

 S No Dia of Bar Load(Tons) Elongation Area of Bar Stress = Load/Area Strain= Elongation/Gauge Length 01 ¾ in 3.68 0 in 0. 441 in2 8.34 Psi 0 02 ¾in 6.84 0 in 0. 441 in2 15.51Psi 0 03 ¾ in 10.28 0 in 0. 441 in2 23.31 Psi 0 04 ¾ in 10.72 1/8 in 0. 441 in2 24.30 Psi 0.0156 05 ¾in 11.82 3/16 in 0. 441 in2 26.80 Psi 0.0234 06 ¾in 12.04 ¼ in 0. 441 in2 27.30 Psi 0.031 07 ¾in 13.04 5/16 in 0. 441 in2 29.56 Psi 0.039 08 ¾in 13.78 7/16   in 0. 441 in2 31.24   Psi 0.054 09 ¾in 14.34 9/16   in 0. 441 in2 32.51 Psi 0.070 10 ¾in 14.88 11/16 in 0. 441 in2 33.74 Psi 0.085 11 ½  in 12.6 (Rupture) -------------- 0. 196 in2 64.28 Psi --------------------- 12 ½  in 15.86 (Ultimate) 2 ¼ in 0. 196 in2 80.91 Psi 0.218