McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
6. Surface Areas and Volumes of Spheres
Continue to next subchapter

Exercise 7 Page 852

The volume of a hemisphere is half the volume of a sphere with the same radius.

3619.1m^3

Practice makes perfect

A hemisphere is the name of a solid that is half of a sphere.

The volume of a hemisphere with radius r is half the volume of a sphere with radius r. Volume of a Hemisphere [0.8em] V=1/2(4/3π r^3) ⇔ V=2/3π r^3 To use this formula we first need to calculate the radius. To do so, we will consider the given fact that the circumference of a great circle is 24πm. Let's recall the formula for the circumference of a circle with radius r. C=2π r We can substitute 24π for C in the above formula and solve for the radius r.

C=2Ï€ r
24Ï€=2Ï€ r
â–¼
Solve for r
24/Ï€=2r
12=r
r=12

The radius measures 12m. We can substitute this value in the formula for the volume of a hemisphere and simplify.

V=2/3Ï€ r^3
V=2/3Ï€ ( 12)^3
V=2/3Ï€ 1728
V=2/31728Ï€
V=3456/3Ï€
V=1152Ï€
V=3619.11...
V≈ 3619.1

The volume of the hemisphere to the nearest tenth is 3619.1m^3.