Presentation on theme: "6-6 Volume of prisms and Cylinders"— Presentation transcript:
1 6-6 Volume of prisms and Cylinders Prism- a three-dimensional figure named for the shape of its bases. The two bases are congruent polygons. All of the other faces are parallelograms.(The top and the bottom are the same. The sides are parallelograms.)Triangular PrismThe bases are shaped like trianglesV= 1/2bh(area of a triangle) x (height)Rectangular PrismThe bases are shaped like rectanglesV= lwh(area of the rectangle) x (height)If there are 5 or more sides to the base, the formula for volume is V=bh.The area of the base will be provided.All you have to do is multiply it by the height.CylinderThe bases are shaped like circlesV= Πr2h(area of the circle) x (height)
2 Example: Find the volume of a rectangular prism with base 2 cm by 5cm and height 3 cm. V= lwhV= (2)(5)(3)V= 30Example: Find the volume.h=12inr=4inV=Πr2hV=3.14(16)(12)V=602.88Example: A juice box measures 3 in. by 2 in. by 4 in. Explain whether tripling the length, width, or height of the box would triple the amount of juice the box holds.First, you have to calculate the volume of the juice box.V= lwhV= 3(2)(4)V= 24in3Next, triple one of the measurements.V=lwhV=9(2)(4)V=72in3If you triple one of the measurements, the entire volume triples. The juice box will hold triple the amount of juice.
3 Example: A juice can has a radius of 2 in. and a height of 5 in Example: A juice can has a radius of 2 in. and a height of 5 in. Explain whether tripling the height of the can would have the same effect on the volume as tripling the radius.First, you have to find the volume of the juice can.V= Πr2hV= 3.14(4)(5)V= 62.8in3Now, triple the height of the can and find the volume.V= 3.14(4)(15)V=188.4in3188.4 ÷ 62.8 = 3 The volume increases by 3 times when you triple the height.Next, you have to triple the radius and find the volume.V=3.14(36)(5)V= 565.2565.2 ÷ 62.8 = 9 When you triple the radius, the volume increases by 9 times.