Perimeter, Are and Volume Flashcards
Area of a circle - formula
Area = Pi x Radius squared
Area of an annulus - formula
Area= Pi x ( Radius (large circle) Squared x radius squared )
Area of a sector - formula
Area = Theta over 360 x Pi x Radius squared
Area of a semicircle - formula
Area = 1/2 x Pi x Radius squared
Area of a quadrant - formula
Area = 1/4 x Pi x Radius squared
Area of composite shapes
- Divide the composite shape into two or more plane shapes.
- Calculate the area of each plane shape.
- Add or subtract the areas of the plane shapes.
- Write the answer to the specified level of accuracy with the correct units.
Area of a trapezium - formula
Area = 1/2 x (a+b)h
= h over 2 (a+b)
Trapezoidal rule
Area = h/2 (df + dt)
Surface area of right prisms
- Visualise the surfaces of the solid. If necessary draw the net of the solid.
- Write a formula for the surface area, using the net as a guide.
- Substitute the values into the formula for the surface area.
- Use your calculator to find the surface area.
- Write the answer to the specified level of accuracy with the correct units.
Surface are of an open cylinder - formula
Surface Area = 2 x Pi x radius x height
Curved Surface = 2 x Pi x radius x height
Surface are of a closed cylinder - formula
Surface Area = 2 x Pi x radius squared + 2 x Pi x radius x height
Area of top = Pi x radius squared
Area of bottom = Pi x radius squared
Curved surface = 2 x Pi x radius x height
Surface area of sphere - formula
Surface Area = 4 time Pi x radius squared
Surface area of open hemisphere - formula
Surface Area = 2 x Pi x radius squared
Surface area of closed hemisphere - formula
Surface Area = 3 x Pi x radius squared
Area of curved surface = 2 x Pi x radius squared
Area of base = Pi x radius squared
Surface area of a square pyramid
The surface area of a pyramid is found by finding the area of each face. For pyramids, the surface area is calculated by adding the area of the base and the area of the triangular faces. To find the area of the triangular face requires the slant height. The slant height of a right pyramid is the distance from the apex to the base, along a triangular face.