Question

the radius of metallic sphere is 9cm it was melted to make the wire of diameter 4 mm find the length of the wire​

Answer 1

As volume remains const.

So

Vol. Of sphere=vol. Of wire(cylinder)

4/3×π×R^3=π×r^2×l

4/3×R^3=r^2×l

l=4×R^3/3×r^2

l=4×9×9×9/3×0.2×0.2

l=24300cm