Question

1. Find the volume and curved surface area of a right circular cylinder of
height 21 cm and base radius 5 cm.
​

Answer 1

Step-by-step explanation:

$volume \: of \: a \: cylinder = \frac{1}{3} \times \pi \times {r}^{2} \times h$

$= \frac{1}{3} \times \frac{22}{7} \times {5}^{2} \times 21 \: cubic \: cm$

$= \frac{1}{3} \times \frac{22}{7} \times 25 \times 21 \: cubic \: cm$

$= 22 \times 25 \: cubic \: cm$

$= 550 \: cubic \: cm$

$curved \: surface \: area \: of \: cylinder \: = 2 \times \pi \times r \times h \: sq.cm$

$= 2 \times \frac{22}{7 } \times 5 \times 21 \: sq.cm$

$= 44 \times 5 \times 3 \: sq.cm$

$= 660 \: sq.cm$