An Important Question of class 10 Based on Mensuration Chapter of M.L Aggarwal for ICSE BOARD.
The radius of a sphere is given in this question. It is melted and drawn into a wire of diameter 2 mm. Find the length of the wire in metres.
This is the Question Number 02, Exercise 17.5 of M.L Aggarwal.
Deepak BoraNewbie
The radius of a sphere is 9 cm. It is melted and drawn into a wire of diameter 2 mm. Find the length of the wire in metres.
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Radius of the sphere, r = 9 cm
Volume of the sphere, V = (4/3)r3
= (4/3)××93
= 12××81
= 972 cm3
Diameter of the wire = 2 mm
So radius of the wire = 2/2 = 1 mm = 0.1 cm
Since the sphere is melted and drawn into a wire, volume remains the same.
Volume of the wire, r2h = 972
×0.12 ×h =972
h = 972/0.12
h = 972/0.01
h = 97200 cm
h = 972 m
Hence the length of the wire is 972 m.