nine:0
9
Four...
As the area of a circle is pi*radius2 the increase in area is a factor of 32. So tripling the radius gives an increase in area by a factor of 9.
The volume increases faster. (proportional to the cube of the radius)The surface area increases slower. (proportional to the square of the radius)
The surface area is reduced by a factor 4, the volume by a factor 8.
9
By a factor of 32 = 9. In general, surface area (for any two similar objects) is proportional to the square of any linear measurement.
Four...
16
As the area of a circle is pi*radius2 the increase in area is a factor of 32. So tripling the radius gives an increase in area by a factor of 9.
The surface of a sphere is: A=4? r2 From this, the surface are changes as the square of the radius. It does not change linearly.
The volume increases faster. (proportional to the cube of the radius)The surface area increases slower. (proportional to the square of the radius)
For any geometric figure, surface area is proportional to (linear dimensions)2 .As the balloon's diameter doubles, its area increases by the factor of (2)2 = 4 .
If the radius of a sphere is doubled, the surface area increases by (2)2 = 4 times, and the volume increases by (2)3 = 8 times.
It remains the same or increases in surface area.
If the radius of a sphere is tripled, the surface area increases by (3)2 = 9 times, and the volume increases by (3)3 = 27 times.
the volume changes as radius squared and linear with height, so tripling radius and double of height gives 3 x 3 x 2 = 18 times more volume