okay I have to find the surface area and volume of a cylinder thats diameter is 4 inches the radius is 2 inches and the height is 1.5 inches .. how do I do that ?
2007-01-07 15:27:25 · 3 answers · asked by Lizzie . ™ 2 in Education & Reference ➔ Homework Help
well how do I find the perimeter of the top of the cylinder ? is that the same thing as the circumferance?
2007-01-07 15:40:39 · update #1
Area of a cylinder= Area of top + Area of bottom + Area of sides
Top bottom: pi*r^2 = 3.14*2*2 = 12.57 square inches each.
circumference of circle = pi*2*r = 12.57 inches again
Side area = 12.57 * 1.5 = 18.86 square inches
Total area: 12.57 + 12.57 + 18.86 = 44 square inches
VOLUME is: Area of top * height
Volume = 12.57 * 1.5 = 18.86 cubic inches
2007-01-07 15:43:24 · answer #1 · answered by Alan 6 · 0⤊ 0⤋
Surface Area of a Cylinder = 2 pi r 2 + 2 pi r h
(h is the height of the cylinder, r is the radius of the top)
Surface Area = Areas of top and bottom +Area of the side
Surface Area = 2(Area of top) + (perimeter of top)* height
Surface Area = 2(pi r 2) + (2 pi r)* h
2007-01-07 23:35:46 · answer #2 · answered by andrew 3 · 0⤊ 0⤋
ok
the easiest way to think about volume is that you are calculating the area of each of the circles that make up the cylinder.
area = pi * r^2
volume = area * height
surface area (assuming there is a top and bottom to the cylinder) = area * 2 + height * perimeter of the circle
2007-01-07 23:35:58 · answer #3 · answered by sadfwer 3 · 0⤊ 0⤋