NON – UNIFORM BENDING – VERIFICATION OF RELATION BETWEEN LOAD AND DEPRESSION USING PIN AND MICROSCOPE
To verify the relation between the load and depression using non-uniform bending of a beam.
A long uniform beam (usually a metre scale), two knife – edge supports, mass hanger, slotted masses, pin, vernier microscope
M/s = a constant
M → Load applied (mass) (kg)
s → depression for the applied load(metre)
· Place the two knife – edges on the table.
· Place the uniform beam (metre scale) on top of the knife edges.
· Suspend the mass hanger at the centre. A pin is attached at the centre of the scale where the hanger is hung.
· Place a vernier microscope in front of this arrangement
· Adjust the microscope to get a clear view of the pin
· Make the horizontal cross-wire on the microscope to coincide with the tip of the pin. (Here mass hanger is the dead load M).
· Note the vertical scale reading of the vernier microscope
· Add the slotted masses one by one in steps of 0.05 kg (50 g) and take down the readings.
· Then start unloading by removing masses one by one and note the readings.
· Subtract the mean reading of each load from dead load reading. This gives the depressions for the corresponding load M.
To find M/s
Load (M) vs Depression (s)
A graph between M and s can be drawn by taking M along X- axis and s along Y – axis.
This is a straight line.
· The ratio between mass and depression for each load is calculated. This is found to be constant.
· Thus the relation between load and depression is verified by the method of non-uniform bending of a beam.