A toy is in the shape of a cylinder surmounted by a hemisphere. The height of the toy is 25cm. Find the total surface area of the toy if its common diameter is 12cm.
ONLY QUALITY ANSWERS. NO COPIED ANSWERS. IF IT IS WRONG THE ANSWERS OF YOURS WILL BE DELETED. SO BE CAREFUL..
Answers
Answer:
★Let r and h be the radius and height of the cylinder respectively.
★Given that, diameter d = 12cm, radius r = 6cm
★Total height of the toy is 25 cm
Therefore, the height of the cylindrical portion = 25 - 6 = 19cm
T.S.A of the toy = C.S.A of the cylinder + C.S.A of the hemisphere + Base Area of the cylinder
= 2πrh + 2πr² + πr²
= πr (2h + 3r) sq.units
= \frac{22}{7} \times 6 \times (38 + 18)=
7
22
×6×(38+18)
= \frac{22}{7} \times 6 \times 56=
7
22
×6×56
= 1056=1056
Therefore, T.S.A of the toy is 1056 cm².
Question:
A toy is in the shape of a cylinder surmounted by a hemisphere. The height of the toy is 25cm. Find the total surface area of the toy if its common diameter is 12cm.
Solution:
T.S.A = C.S.A of hemisphere + C. S. A of cylinder + πr²
= 2πr² + 2πrh + πr²
= πr [2r + 2h + r ]
= 22/7 × 6 [2×6+2×19+6]
=22/7 × 6 [12+38+6]
=22/7 × 6 × 56
By canceling 7 and 56, we get:
1056cm³
Therefore, T.S.A of the toy is 1056 cm³.