Question

A rocket is in the form of a right circular cylinder closed at the lower end a surmounted by a cone with the same radius as that of the cylinder . The diameter of the height of the cylinder are 6cm and 12 cm respectively . If the slant height of the conical portion is 5cm find the total surface area and the volume of the rocket.

Answer 1

Please find the attachment

Answer 2

Answer:

Slant height of cone = 5 cm

Diameter of cone = 6 cm

Radius of cone = 3 cm

Curved surface area of cone = $\pi r l = 3.14 \times 3 \times 5 = 47.1 cm^2$

Radius of cylinder = 3 cm

Height of cylinder = 12 cm

Area of cylinder with one base = $2 \pi r h + \pi r^2 = 2 \times 3.14 \times 3 \times 12 +  3.14 \times 3^2=254.34cm^2$

Total surface area = 254.34+ 47.1  = 301.44 sq.cm.

Volume of rocket = $\pi r^2 h + \frac{1}{3} \pi r^2 h=3.14 \times 3^2 \times 12+ \frac{1}{3} \times 3.14 \times 3^2 \times 12=452.16 cm^3$

Hence the total surface area and volume is 254.34 sq.cm. and 452.16 cubic cm respectively