Question

The length of a melallic wire is 3m and its diameter is 4mm. If the wire is extended so that its length becomes 3.5m. Find the new radius of wire.

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Answer 1

Answer:

It will be 2.27 mm (approx.).

Step-by-step explanation:

If the diameter is 4 mm then the radius will be 2 mm (Since radius=diameter/2). now, the volume of a cylinder with radius 2 mm & height 4 mm will be:

Volume=πr^2h

            =22/7X2X2X4

            =50.27 (approx.)

Now, the radius= root over (volume/πh)

                          =root over {50.27/(22/7)X4), which is 2.27 mm approximately.