A wooden toy rocket is in the shape of a cone mounted on a cylinder as shown in fig. The base of conical part is 6cm, while the base diameter of
cylindrical portion is 4cm. The rocket is to be painted, find the area to be painted.
Answers
Step-by-step explanation:
Area to be painted orange = Curved surface area of the cone + Base area of the cone − Base area of the cylinder
Area to be painted yellow = Curved surface area of the cylinder + Area of one bottom base of the cylinder
Curved surface area of cone =πrl
l=
6
2
+2.5
2
l=
36+6.25
l=
42.25
l=6.5 cm
Curved surface area of cone =3.14×2.5×6.5
=51.025 cm
2
Base area of cone = Area of circle
=πr
2
=3.14×(2.5)
2
=3.14×6.25
=19.625 cm
2
Curved surface area of cylinder =2πrh
=2×3.14×1.5×20
=188.4 cm
2
Base area of cone = Area of circle
=πr
2
=3.14×(1.5)
2
=7.065 cm
2
Area to be painted orange = Curved surface area of the cone + Base area of the cone − Base area of the cylinder
=51.025+19.625−7.0625
=63.59 cm
2
Area to be painted yellow = Curved surface area of the cylinder + Area of one bottom base of the cylinder
=188.4+7.065
=195.465 cm
2
Hence,
Area to be painted orange =63.59 cm
2
Area to be painted yellow =195.465 cm
2
Hence,
Area to be painted orange =63.59 cm
2
Area to be painted yellow =195.465 cm
2