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A steel ball (density ρsteel = 7200 kg/m3) is placed in an upward moving liquid AI (density ρal = 2360 kg/m3, viscosity μAl = 1 × 10-3 Pa.s and Reynolds number = 5 × 105). The force (F) exerted on the steel ball is expressed as F = fπR2(ρAl V2/2)
where, f is friction factor (= 0.2), v is the velocity of liquid AI and R is the radius of steel ball.
The force exerted on the steel ball is

A steel ball (density ρsteel = 7200 kg/m3) is placed in an upward moving liquid AI (density ρal = 2360 kg/m3, viscosity μAl = 1 × 10-3 Pa.s and Reynolds number = 5 × 105). The force (F) exerted on the steel ball is expressed as F = fπR2(ρAl V2/2)
where, f is friction factor (= 0.2), v is the velocity of liquid AI and R is the radius of steel ball.
The force exerted on the steel ball is Correct Answer 8.32 N

Related Questions

Molten steel is kept in a ladle. Due in natural convection. mixing occurs inside the melt. A 1cm diameter sphere is held in the centre of the melt where the steel flows upward. so as to measure the force exerted by the melt on the sphere. The force. F exerted by the melt on the sphere is given by $$F = f\left( {\frac{\pi }{8}} \right).\left( {\frac{{{\mu ^2}}}{8}} \right){\left( {\operatorname{Re} } \right)^2}.$$
Data: Density of liquid steels
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Viscosity of liquid steel
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Reynolds number (Re) of the melt
= 5 × 103
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