A cylindrical motor of height 12cm has uniform thickness of 2cm. If the diameter of its outer cross section is 10cm, Find the volume of the constituent material. (take \(\pi\) = \(\frac{22}{7}\)

A.

\(\frac{6600}{7}\)cm3

B.

270cm3

C.

660cm3

D.

\(\frac{4224}{7}\)cm3

E.

\(\frac{1980}{7}\)cm3

Correct answer is D

V = \(\pi\)r2h

= \(\frac{22}{7}\) x 52 x 12 - \(\frac{22}{7}\) x 32 x 12

= \(\frac{22}{7}\) x 12(52 - 32)

= \(\frac{4224}{7}\)