Question

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

Answer 1

Given: 
Rectangular strip has radius, r = 7 cm
Height, h = 25 cm
\[\text{ Volume of the solid, V }= \pi r^2 h\]
\[ = \frac{22}{7} \times 7^2 \times 25\]
\[ = 3850 {cm}^3\]