how would you work out a cylinder with the radius of 55cm and the length of 1.5m
If you have a cylinder and know its radius and its length, then there are two things you can work out.
1) its volume
2) it surface area.
1)
Volume is given by, V = πR^2.L,
where R is the radius and L is the length.
We have R = 55 cm = 0.55 m, and L = 1.5 m. Then
V = πR^2.L = π(0.55)^2(1.5) = 0.45375π
Volume is: V = 0.45375π m^3
2)
If the cylinder is a solid one, then surface area is the area of the curved surface plus the area of the two circular ends.
A = 2πR.L + 2(πR^2)
A = 2π(0.55).1.5 + 2(π(0.55)^2)
A = 2π{0.55).1.5 + (0.55)^2}
A = 2π(0.55){1.5 + 0.55}
A = 2π(0.55){2.05}
A = 2.255π
Surface area is: A = 2.255π m^2
If the cylinder is hollow, only the curved surface counts. Then
A = 2πR.L
A = 2π(0.55).1.5
A = 1.65π
Surface area is: A = 1.65π m^2