Question

please solve it questions no 8

Answer 1

This is your figure:

Here, r = 5/ 2 cm = 2.5 cm = 0.025 m, h = 28 m. 

Total radiating surface in the system = total surface area of the cylinder 

= $2 \pi r(h+r)$

= 2 × 22/ 7 × 0.025 (28 + 0.025) $m^{2}$

= $\frac{44*0.025*28.025}{7}$ $m^{2}$= 4.4 $m^{2}$ (approx) Ans

Answer 2

I hope this will help u !!