Question

Why dead load is attached to wire initially searle's apparatus ?

Answer 1

Two indentical wires A and B are suspended from a rigid support so that the point ka suspension are very close to each other. searle's apparatus blocks are attached to the lower ends of the wiers by means of chucks F1 and F2 Searle's apparatus blocks consist of two metal frames P and Q . the two frames are loosely connected by cross strips in such a way that the frame Q can move relatively with respect frame P A spirit level S is hinged to the frame P and is rested on the tip of a micromeer screw M which can work in a nut fixed in the frame Q
At the lower end each frame carries a hanger from which slotted weight can be suspended. wire A is a dummy wire from which a fixed load of about 1 kg ( dead weight ) is suspended

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