+1713 The surface area of a sphere with the radius r is 4 pi r^2. Including the area of its circular base, what is the total surface area of a hemisphere with the radius 6 cm? Express your answer in terms of pi.
Work/confusion:
I know that a hemisphere is half a sphere, so I cut the equation in half, which got me to:
4∗pi∗r22=2∗pi∗r2
After that, I have NO idea what to do...
Edit: I do, but I want to make sure I'm right so far
A hint, please?
+1713 Wait: Don't I need to calculate the circle:
so that would be
2pir
12pi+72pi
84pi?
+37168 Don't overthink it...... if total surface area is 4 pi r^2 you want 1/2 of this 2 pi r^2 = 72 pi
The way the question is worded is a bit unclear.....I think you may be right, you will need to add the area of the base (the' cut' area of the sphere)
(pi r^2) (2 pi r is the circumference)
+15088 The surface area of a sphere with the radius r is 4 pi r^2. Including the area of its circular base, what is the total surface area of a hemisphere with the radius 6 cm? Express your answer in terms of pi.
Die Oberfläche einer Kugel mit dem Radius r beträgt 4 pir ^ 2. Wie groß ist die Gesamtfläche einer Halbkugel mit einem Radius von 6 cm einschließlich der Fläche ihrer kreisförmigen Basis? Drücken Sie Ihre Antwort in Form von pi aus.
Hello tommarvoloriddie!
Ahemisphere=12⋅Asphere+AcircleAhemisphere=4⋅π⋅r22+π⋅r2Ahemisphere=3⋅π⋅r2
Ahsph r=6cm=3⋅π⋅(6cm)2=108cm2⋅π=339.292cm2
!
