Question

5. A glass jar has a plastic lid. The jar and the lid are both cylindrical. The radius and the height of the jar are 3.5 cm and 10 cm and those of the lid are 3.6 cm and 1.3 cm. Find the surface area of the glass and of the plastic lid separately. HOTS​

Answer 1

Answer:

If the height and radius of a cylindrical jar is 10 cm and 3.5 cm respectively and that of a lid is 1.3 cm and 3.6 cm respectively, then their surface areas are $297cm^{2}$ and $110.88 cm^{2}$ respectively

Step-by-step explanation:

Given

The radius of jar = 3.5 cm

Height of the jar = 10 cm

The surface area of the jar =

$2\pi r(r+h)\\\\= 2*\frac{22}{7} *3.5(3.5+10)\\\\=2*22*0.5(13.5)\\\\=2*11*13.5\\\\=297cm^{2}$

Radius if the lid= 3.6cm

Height of the lid=1.3cm

The surface area of the lid=

$2\pi r(r+h)\\\\= 2*\frac{22}{7} *3.6(3.6+1.3)\\\\=2*\frac{22}{7} *3.6*4.9\\\\=2*22*3.6*0.7\\\\= 110.88 cm^{2}$

So surface area of the jar is $297 cm^{2}$ and that of the lid is $110.88cm^{2}$