Question

A rectangular strip 25 cm × 7 cm is rotated about the longer side. Find the volume of the solid, thus generated.

Answer 1

$$\begin{gathered} \mathrm{Given}: \\ \mathrm{Rectangular}\mathrm{strip}\mathrm{has}\mathrm{radius},r=7\mathrm{cm} \\ \mathrm{Height},h=25\mathrm{cm} \\ \mathrm{Volume}\mathrm{of}\mathrm{the}\mathrm{solid},\mathrm{V}=\mathrm{\pi }{r}^{2}h \\ =\frac{22}{7}\times 7^2\times 25 \\ =3850{\mathrm{cm}}^3 \end{gathered}$$