Monday, April 14, 2008

Judy's BOB

THE SURFACE AREA OF A RECTANGULAR PRISM
1.what is surface area?
surface area is the total area of the outside of a 3-D shape

2. how do you find the surface area?

first take your shape, and draw what it
would look like if it were opened and laid out:

Then measure the sides,
and find the area of each separate square (or rectangle)
.... suppose the sides are all 2cm long.
The formula to find the area of a square is
Length x Width so the area of each square would be 4cm²

Finally, use the formula to find the surface area.

you can either use:

(area = a)
a+a+a+a+a+a= surface area

4cm²+4cm²+4cm²+4cm²+4cm²+4cm²= 24cm²
OR
2 (HxL)+ 2(HxW)+ 2(LxW)
2(2x2)+ 2(2x2)+ 2(2x2)
2(4)+2(4)+2(4)=
8cm+8cm+8cm= 24cm²
------------------------------------------------------------------------------------------------
THE VOLUME OF A RECTANGULAR PRISM

1. what is volume?
the amount of space an object takes up. in this case, a rectangular prism

2. How do you find the volume?

take a rectangular prism, and measure
it's length, width, and depth (also called height)

Then use the formula to find out the volume. You can use:

length x width x depth
3cm x 5cm x 2 cm
=30cm
³
OR
Area of base x depth
(3cm x 5cm) x 2cm
15cm
² x 2cm= 30cm³

1 comment:

Akytrap said...

Great job i liked how you showed the befor and after pictures when you drew your net. :):):):)