Question
Work out the surface area of following shape (use $\pi = 3.14).$
✓
Answer
In the given figure, there is a cube of side $5\ cm$ and a cylinder of hight $20\ cm$ and radius is $2\ cm.$
So, total surface area = Surface area of cube + Curved surface area of cylinder
$=6(5)^2+2\pi(2)\times20 [\because\text{}$ surface area of cube $= 6a^2]$ $ [\therefore$ surface area of cylinder $=2\pi\text{rh}]$
$=150+80\pi$
Total surface aera $= 150 + 251.2 = 401.2cm^2$
Note: In this question assume that cylinder is at end open.
So, total surface area = Surface area of cube + Curved surface area of cylinder
$=6(5)^2+2\pi(2)\times20 [\because\text{}$ surface area of cube $= 6a^2]$ $ [\therefore$ surface area of cylinder $=2\pi\text{rh}]$
$=150+80\pi$
Total surface aera $= 150 + 251.2 = 401.2cm^2$
Note: In this question assume that cylinder is at end open.
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