Question

A task was assigned to Virat to measure a snake-like steel rod which looks something like this.

Which of the following objects/methods should he use to make this measurement?

• A. A thread and a ruler
• B. Meter scale
• C. Pieces of marbles whose length is known
• D. It is impossible to measure the length of a curved line

Answer 1

The correct option is A

A thread and a ruler

Virat cannot use a meter scale as it cannot be bent along the curve. If he uses pieces of marbles, there will always be some gaps left between two marbles. A thread and ruler can be used to measure the required length. The thread is outlined with the curve as shown in the diagram below and then the thread can be straightened and measured with the help of ruler.