had the diameter of asphere been decreased by 2 cm .it's surfac
e area would have diminished by 113.04 cm. find the surface area of the sphere
Answers
Answered by
0
Answer:
sup dj cm dj DC HC dj HD dj HD ei it we be ah ah
Answered by
0
Answer:
The radius then decreases by 1 cm
4πR2 - 4π(R - 1)2 = 113.04
R2 - R2 + 2R - 1 = 113.04/(4π) = 8.9954
2R - 1 = 8.9954
R = (1+8.9954)/2 = 4.9977
The original surface area was
4πR2 = 4π(4.9977) cm2 = 62.803 cm2
OR:
The surface area of a sphere is
A = 4πr2
Write this in terms of diameter, d.
r = d / 2
A = 4π(d / 2)2
A = 4π(d2 / 4)
A = πd2
We know that if we decrease the diameter, we also decrease the area.
A - 113.04 = (d - 2)2 π
Similar questions