Find curved surface area and total surface of a cylinder when r = 7 and h = 12 cm
Answers
Curved surface area
=2πrh
=2π×12×7
=168π=168×
7
22
=24×22=528cm
2
Total surface area
=CSA+2πr
2
=528+2π×7×7
=528+(2×7×22)
=528+308=836cm
2
Given :
➡️ Radius of base of cylinder (r) = 7 cm
➡️ Height of cylinder (h) = 12 cm
To find :
➡️ Curved surface area of cylinder
➡️ Total surface area of cylinder
Formula used :
▶️Curved surface area of cylinder (C.S.A)= 2πrh
▶️Total surface area of cylinder (T.S.A)= 2πrh + 2πr²
Where :-
⏺️r = radius of base
⏺️h = height of cylinder
⏺️π = 22/7
Solution :
r = 7 and h = 12 cm
=> C.S.A= 2πrh
=> C.S.A= 2 × (22/7) × 7 × 12
=> C.S.A= 2 ×22 × 12
=> C.S.A= 44 × 12
=> C.S.A= 528 cm²
Now , we will find out total surface area.
=> Total surface area of cylinder( T.S.A) = 2πrh + 2πr²
=> T.S.A = C.S.A + 2πr²
=> T.S.A = 528 + 2× (22/7)× (7)²
=> T.S.A = 528 + 2× (22/7)× 7×7
=> T.S.A = 528 + (2× 22×7)
=> T.S.A = 528 +308
=> T.S.A = 836 cm²
Answer :
▶️Curved surface area of cylinder = 528 cm²
▶️ Total surface area of cylinder = 836 cm²
Learn More :
Volume of cylinder = πr²h
T.S.A of cylinder = 2πrh + 2πr²
Volume of cone = ⅓ πr²h
C.S.A of cone = πrl
T.S.A of cone = πrl + πr²
Volume of cuboid = l × b × h
C.S.A of cuboid = 2(l + b)h
T.S.A of cuboid = 2(lb + bh + lh)
C.S.A of cube = 4a²
T.S.A of cube = 6a²
Volume of cube = a³
Volume of sphere = (4/3)πr³
Surface area of sphere = 4πr²
Volume of hemisphere = ⅔ πr³
C.S.A of hemisphere = 2πr²
T.S.A of hemisphere = 3πr²
