Surface Area of Cylinders Practice

1 answer

Sure! To calculate the surface area of a cylinder, you need to know two measurements: the radius (r) of the base and the height (h) of the cylinder.

The formula for the surface area (SA) of a cylinder is:

\[ SA = 2\pi r(h + r) \]

This formula accounts for the area of the two circular bases and the area of the curved surface.

  1. Area of the two bases: \( 2\pi r^2 \)
  2. Area of the curved surface: \( 2\pi rh \)

Putting it all together gives you the total surface area:

\[ SA = 2\pi r^2 + 2\pi rh = 2\pi r(h + r) \]

Let's practice with some examples!

Example 1:

  • Radius (r) = 3 cm
  • Height (h) = 5 cm

Calculate the surface area.

Example 2:

  • Radius (r) = 4 m
  • Height (h) = 10 m

Calculate the surface area.

Solutions:

Example 1:

  1. Calculate the surface area using the formula: \[ SA = 2\pi(3)(5 + 3) \] \[ SA = 2\pi(3)(8) \] \[ SA = 48\pi \approx 150.8 \text{ cm}^2 \]

Example 2:

  1. Calculate the surface area: \[ SA = 2\pi(4)(10 + 4) \] \[ SA = 2\pi(4)(14) \] \[ SA = 112\pi \approx 351.9 \text{ m}^2 \]

Feel free to try your own examples or ask for more practice problems!