If the curved surface of right circular cylinder inscribed in a sphere...
Explanation:We are given a right circular cylinder inscribed in a sphere of radius r. We need to find the height of the cylinder such that the curved surface area of the cylinder is maximum.
Let's consider a cross-section of the cylinder and the sphere that contains it.
Step 1: Deriving the Formula for Curved Surface Area of CylinderThe curved surface area of the cylinder is given by:
C.S.A. = 2πrh
where r is the radius of the cylinder and h is the height of the cylinder.
Step 2: Deriving the Formula for Radius of CylinderThe radius of the cylinder can be found using the Pythagorean theorem as follows:
r^2 + h^2 = (2r)^2
Simplifying the above equation, we get:
h^2 = 3r^2
Therefore, the radius of the cylinder is:
r = h/√3
Step 3: Deriving the Formula for Curved Surface Area of Cylinder in terms of hSubstituting the value of r in the formula for C.S.A., we get:
C.S.A. = 2πrh = 2π(h/√3)h = (2π/√3)h^2
Step 4: Finding the Maximum Value of C.S.A.To find the maximum value of the curved surface area, we differentiate the formula for C.S.A. with respect to h and equate it to zero.
d/dh [(2π/√3)h^2] = (4π/√3)h = 0
Solving the above equation, we get:
h = √2r
Therefore, the height of the cylinder that maximizes the curved surface area is √2r.
Conclusion:Hence, we have shown that the height of the cylinder is √2r when the curved surface area of the cylinder is maximum.