Page 151 - Physics - XI

7. After taking 6–7 readings, start unloading of weights one by one and take observations again on the
vertical scale.

8. Note all the observations in the observation table.
(ii) When metre scale is loaded in the middle.
9. Find the position of centre of gravity of metre scale by placing it on a sharp wedge. Place the metre
rod symmetrically on the two knife edges keeping them about 80 cm apart and see that the metre rod

is perfectly horizontal.
10. Fix a pointer at the midpoint of the metre scale (between the two knife edges) with the help of wax or
adhesive tape.
11. Now, repeat the steps 3 to 7 and record all the observations in the observation table.

Observations
(i) For study of load-depression relationship when metre rod is loaded at its end
Initial reading on vertical scale when there is no load at the free end = y = ..... cm
0
Table for calculation of load and depression when metre rod is loaded at its end

S. No. Load suspended Vertical scale reading (cm) Depression
Loading Unloading Mean δ = (y – y)
(g wt) 0
y 1 y 2 y+ y 2 (cm)
1
y=
2
1.

2.
3.

4.
5.

6.

(ii) For study of load-depression relationship when metre rod is loaded in the middle
Initial reading on vertical scale when there is no load at the middle = y = ..... cm
0
Table for calculation of load and depression when metre rod is loaded in the middle
S. No. Load suspended Vertical scale reading (cm) Depression

(g wt) Loading Unloading Mean δ = (y – y)
0
y y y+ y 2 (cm)
1
1 2 y=
2
1.
2.
3.
4.
5.
6.

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