How to Use
Direct mode
Type the known quantity with its parameter name:
sphere(r=5) → radius = 5
sphere(d=10) → diameter = 10
sphere(c=31.416) → circumference
sphere(a=314.16) → surface area
sphere(v=523.6) → volume
Interactive mode
Type sphere and press ENTER. The calculator will ask which quantity is known (r, d, c, a, or v), then prompt for its value.
Example
sphere(r=5) returns:
Diameter = 10
Circumference = 31.415927
Surface area = 314.15927
Volume = 523.59878
Precision
Press FIX 2 (FIX key then 2) to round results to 2 decimal places. Press SHIFT FIX (CLRFIX) to restore full precision.
Formulas
Circumference
C = 2 × π × r
Surface area
A = 4 × π × r²
Volume
V = (4/3) × π × r³
Radius from volume
r = ∛(3V / (4π))
Radius from surface area
r = √(A / (4π))
Radius from circumference
r = C / (2π)