Question

In Searle's apparatus we have two wires. During experiment we study the extension in one wire. The use of second wire is-

• A. to support the apparatus because it is heavy and may not break single wire
• B. to compensate the changes in length caused by changes in temperature of atmosphere during experimentation
• C. to keep the apparatus in level so that extension is measured accurately
• D. all the three above

Answer 1

The correct option is B to compensate the changes in length caused by changes in temperature of atmosphere during experimentation

Frist wire : extension due to applied load.

Second wire : to study the effect of temperature and atmospheric conditions.

Therefore, Answer is (B)