A sphere with a radius of 2 cm has a surface area of
- 8pi cm^2.
- 16pi cm^2.
- 64pi cm^2.
Explanation from PART66Online
The surface area of a sphere is 4*pi*r squared. With a radius of 2 cm, r squared is 4, so the area is 4*pi*4 = 16*pi square centimetres. The 64*pi result mistakenly uses the volume idea or cubes the radius instead of squaring it.
D
DanailPS asked · 30 Jan 2020
Why
Community Comments (2)
Q
qlwjqthrdlst
7 Feb 2020
S= 4pi r^2
S=4pi*(2cm)^2
S=4pi*4cm^2
S=16pi cm^2
S=4pi*(2cm)^2
S=4pi*4cm^2
S=16pi cm^2
J
Jordi
9 Feb 2020
First you need to know that the formula which gives us the surface area of a circle is A=4πr^2.Then you just need to place the number 2 into the formula without changing the pi and then you have 2*2*pi*4=16pi.
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