Q. 24.1( 8 Votes )

# A wire was bent into a circle of diameter 4 centimetres. What would be the diameter of a circle made by bending a wire of half the length?

Answer :

Diameter of circle = 4 cm

Length of wire = Circumference of circle

If r = radius of circle

Circumference of circle = 2 × π × r=2 × π × 4

=8 × π

If length of wire is halved,

Circumference is also halved

∴ New Circumference = 1/2 × (8 × π)= 4 × π

Let r^{’}be new radius

∴ 2 × π × r'= New Circumference = 4 × π

∴ r^{’} =

Hence, New diameter = 2 × r'= 2 × 2=4 cm

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