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## Procedure for Simulation

- Select the environment and material for doing experiment.
- Adjust length, breadth and thickness of the material bar using sliders on the right side of the simulator .
- Fix the distance between knife edges and weight hangers using sliders.
- Focussing the microscope using focussing knob and adjusting the tip of the pin coincides with the point of intersection of the cross wires using left and top knobs on microscope respectively.
- Readings are noted using the microscope reading for 0g. Zoomed part of microscope scale is available by clicking the centre part of the apparatus in the simulator. Total reading of microsope is MSR+VSR*LC. MSR is the value of main scale reading of the microsope which is coinciding exacle with the zero of vernier scale. One of the division in the vernier scale coincides exactly with the main scale is the value of VSR. LC is the least count.
- Weights are added one by one say 50g, then pin moves downwards while viewing through microscope. Again adjust the pin such that it coincides exactly with the cross wire.
- Note the microsope reading and repeat 7 and 8 by increasing the weights.
- The readings are tabulated and Y is determined using equation (3).

## Procedure for Real lab

### Uniform Bending

The bar is placed symmetrically on two knife edges. Two weight hangers are suspended at equal distance from the knife edges. The distance *l* between knife edges and distance p of the weight hanger from knife edges are measured. A pin is fixed vertically at the midpoint of the bar with its pointed end upwards. The microscope is arranged in front of the pin and focused at the tip of the pin. The slotted weights are added one by one on both the weight hangers and removed one by one a number of times, so that the bar is brought into an elastic mood. With the some "dead load" W_{0} on each weight hanger, the microscope is adjusted so that the image of the tip of the pin coincides with the point of intersection of cross wires. The reading of the vernier scale and vernier of microscope are taken. Weights are added one by one and corresponding reading are taken. From these readings, the mean elevation (e) of the mid-point of the bar for a given mass is determined. The value of is calculated . The breadth of the bar (b) is measured by using vernier calipers and thickness of the bar (d) is measured by using screw gauge. Hence calculate the Young's modulus of the material bar.

### Observations and Calculations of Uniform Bending

Value of 1 m.s.d = 1/20

Number of divisions on the vernier, n = 50

Least count of microscope = 1 m.s.d/n = 1/1000 = 0.001 cm

Thickness of the material bar “d” = ……………………….. mm

Breadth of the material bar “b” = ……………………………cm

Mean value of pl^{2}/e = ………………………….m

Load applied for elevation“e” = ………………………… m

Young’s modulus of the material bar ,= …………………………Nm^{-2}

Example: For uniform bending for wood, p=0.5m, m= 0.02kg, g=9.8ms^{-2}, pl^{2}/e = 2.165 m^{2}, b=2.956 x 10^{-2}m,d=50693 x 10^{-3}m.

Y = 1.1 x 10^{10 }Nm^{-2}

Result

1.Young’s modulus of the given material using uniform bending method= …………………………. Nm^{-2}.