A conical vessel of radius 6 cm and height 8 cm is completely filled with water. A sphere is lowered into the water such that when it touches the sides, it is just immersed.What fraction of water overflows?
Answers
Answer:
3:8
Step-by-step explanation:
Let AM = 8 cm, MB = 6 cm.
From figure:
(i)
In ΔAMB,
AB² = AM² + MB²
= 8² + 6²
= 100 cm.
AB = 10 cm.
∴ CB is tangent at M and AB is tangent to P.
⇒ PB = MB = 6
⇒ AP = AB - PB
= 10 - 6
= 4 cm.
Let r be the radius of the circle,
OP = OM = r.
∴ AO = AM - OM
= 8 - r
(ii)
In ΔOAP,
OA² = AP² + OP²
⇒ (8 - r)² = 4² + r²
⇒ 64 + r² - 16r = 16 + r²
⇒ 48 = 16r
⇒ r = 3 cm.
∴ Volume of the sphere = Volume of water which overflows:
= (4/3) πr³
= (4/3) * π * (3)³
= 36π cm³.
∴ Volume of water in the cone before immersing the sphere = Volume of cone
= (1/3) * π * (6)² * 8
= 96 π cm³.
∴ Fraction of water overflows = 36π/96π
= 3/8
= 3 : 8.
Therefore, Fraction of water overflows = 3 : 8.
Hope it helps!