Question

find the volume of the ring of outer radius 14cm and inner radius 7cm​

Answer 1

we have to find the volume of the ring of outer radius 14 cm and inner radius 7 cm.

solution : here outer radius, R = 14 cm

inner radius, r = 7 cm

so diameter of ring = 14cm - 7cm =7cm

radius of ring, t = 3.5cm

if we open the ring, we get a cylinder of length = 2πR

length, l = 2πR = 2 × 22/7 × 14 = 88 cm

volume of ring = volume of cylinder of length l

= πr²l

= 22/7 × 3.5 × 3.5 × 88 cm³

= 22 × 0.5 × 3.5 × 88 cm³

= 3388 cm³

Therefore the volume of ring would be 338 cm³