Question

The external radius of a pipe of metal is \( 4 \) cm and internal radius is \( 3 \) cm. If its length is \( 10 \) cm, then the volume of metal is:

• A. \( 120 \) cm\(^3\)
• B. \( 220 \) cm\(^3\)
• C. \( 440 \) cm\(^3\)
• D. \( 1540 \) cm\(^3\)

Hint:

For hollow cylinders, volume is: \[ V = \pi h (R^2 - r^2) \]

Answer 1

The Correct Option is B

Volume of a cylindrical pipe is given by:
\[ V = \pi h (R^2 - r^2) \] \[ V = 3.14 \times 10 \times (4^2 - 3^2) \] \[ V = 3.14 \times 10 \times (16 - 9) \] \[ V = 3.14 \times 10 \times 7 \] \[ V \approx 220 \text{ cm}^3 \]