# Torus

on . Posted in Solid Geometry

• Torus (a three-dimensional figure) has a shape like a donut.

## Hole Radius of a torus formula

$$\large{ R_h = R - r }$$
Symbol English Metric
$$\large{ R_h }$$ = radius of the hole $$\large{ in }$$ $$\large{ mm }$$
$$\large{ r }$$ = radius of sphere $$\large{ in }$$ $$\large{ mm }$$
$$\large{ R }$$ = radius of center of sphere $$\large{ in }$$ $$\large{ mm }$$

## Surface Area of a torus formula

$$\large{ S = 4 \; \pi^2 \; R\; r }$$
Symbol English Metric
$$\large{ S }$$ = surface area $$\large{ in^2 }$$ $$\large{ mm^2 }$$
$$\large{ \pi }$$ = Pi $$\large{3.141 592 653 ...}$$
$$\large{ r }$$ = radius of sphere $$\large{ in }$$ $$\large{ mm }$$
$$\large{ R }$$ = radius of center of sphere $$\large{ in }$$ $$\large{ mm }$$

## Volume of a torus formula

$$\large{ V = 2 \; \pi^2 \; R\; r^2 }$$
Symbol English Metric
$$\large{ V }$$ = volume $$\large{ in^3 }$$ $$\large{ mm^3 }$$
$$\large{ \pi }$$ = Pi $$\large{3.141 592 653 ...}$$
$$\large{ r }$$ = radius of sphere $$\large{ in }$$ $$\large{ mm }$$
$$\large{ R }$$ = radius of center of sphere $$\large{ in }$$ $$\large{ mm }$$