Geometry Test #11 Flashcards
Degrees into Radians
π/180
Radians into Degrees
180/π
Arc Sector Area
(x/360)πr^2
Arc Sector Length
(x/360)2πr
TA (prism)
LA+2B
TA (pyramind)
LA+B
LA (right prism)
ph
V (right prism)
BH
LA (pyramid)
(1/2)pℓ
V (pyramid)
(1/3)Bh
LA (cylinder)
2πrh
V (cylinder)
hπr^2
LA (cone)
πrℓ
V (cone)
(1/3)πr^2h
A (sphere)
4πr^2
V (sphere)
(4/3)πr^3
If the scale factor of two similar solids is a:b. then
(1) the ratio of corresponding perimeters is
(2) the ratio of the base areas, of the lateral areas, and of the total areas is
3) the ratio of the volumes is
1) a:b
2) a^2:b^2
3) a^3:b^3
Cross sections
The 2-dimensional figure created when a plane intersects a solid (dependent on the angle at which the plane intersects the solid).
Cavalier’s Principle
If 2 solids share the same height and the corresponding cross sections of the solids have equal area, then the solids have equal volume. (same height, same base (thus = cross sections) and thus equal).
arc length=
radius(angle)
TA (cylinder)
2(pi)(r)(h)+2(pi)(r^2)
Mass=Weight
Density*Volume
Density=
Mass/Volume
Total population=
(Pop Density)(Area)
Total Cost
(cost per unit area/volume)(area/volume)
