Question

In: Mechanical Engineering

A 4 mm-diameter spherical raindrop falls freely in standard atmosphere. (a) Sketch a FBD and derive...

A 4 mm-diameter spherical raindrop falls freely in standard atmosphere. (a) Sketch a FBD and derive an equation for determining the terminal velocity. (b) Determine the terminal velocity. (c) Repeat (a) if the diameter is halved.

Solutions

Expert Solution


Related Solutions

A spherical raindrop 2.1 mm in diameter falls through a vertical distance of 3650 m. Take...
A spherical raindrop 2.1 mm in diameter falls through a vertical distance of 3650 m. Take the cross-sectional area of a raindrop = πr2, drag coefficient = 0.45, density of water to be 1000 kg/m3, and density of air to be 1.2 kg/m3. (a) Calculate the speed a spherical raindrop would achieve falling from 3650 m in the absence of air drag. (b) What would its speed be at the end of 3650 m when there is air drag? (Note...
A spherical raindrop 2.7 mm in diameter falls through a vertical distance of 5000 m. Take...
A spherical raindrop 2.7 mm in diameter falls through a vertical distance of 5000 m. Take the cross-sectional area of a raindrop = πr2, drag coefficient = 0.45, density of water to be 1000 kg/m3,and density of air to be 1.2 kg/m3. (a) Calculate the speed a spherical raindrop would achieve falling from 5000 m in the absence of air drag. 313.04 m/s (correct) (b) What would its speed be at the end of 5000 m when there is air...
Consider a 4-mg raindrop that falls from a cloud at a height of 2 km. Part...
Consider a 4-mg raindrop that falls from a cloud at a height of 2 km. Part a) If we neglect air resistance, what would be the speed of the raindrop when it reaches the ground? Assume that the falling raindrop maintains its shape so that no energy is lost to the deformation of the droplet. ________ m/s Part b) When the raindrop reaches the ground, it won't kill you or even bruise you because its terminal velocity is just 10...
Spherical particle of silica of 0.1mm diameter falls in water filled in a glass cylinder of...
Spherical particle of silica of 0.1mm diameter falls in water filled in a glass cylinder of 40 mm internal diameter. Estimate the terminal settling velocity of single particle of silica. Also calculate the terminal settling velocity of silica particles when mass ratio of water to silica is 5. .
A pipe, 900 m long and 200 mm in diameter discharges water to the atmosphere at...
A pipe, 900 m long and 200 mm in diameter discharges water to the atmosphere at a point 10 m below the inlet level. With an inlet pressure of 40 kPa gauge, the flow rate is 40 litres/sec. At a point half way between the pipe inlet and outlet, a new tapping is made from which water is taken at a rate of 18 litres/sec. To what value must the inlet pressure be raised in order to maintain the same...
A spherical thermocouple junction 1.0 mm in diameter is inserted in a combustion chamber to measure...
A spherical thermocouple junction 1.0 mm in diameter is inserted in a combustion chamber to measure the temperature ?T? of the products of combustion. The hot gases have a velocity of V= 5 m/s. (a) If the thermocouple is at room temperature, Ti,when it is inserted in the chamber, estimate the time required for the temperature difference, ?T?-T, to reach 2% of the initial temperature difference, ?T?-Ti. Neglect radiation and conduction through the leads. Properties of the thermocouple junction are...
Q. Spherical glass particles (12 mm diameter and 2500 kg/m 3 density) and spherical metal particles...
Q. Spherical glass particles (12 mm diameter and 2500 kg/m 3 density) and spherical metal particles (1.5 mm diameter and 7500 kg/m3) are falling in water (density= 1000 kg/m3) . (1) Calculate the terminal falling velocities of glass and metal particles in water for a constant friction factor of 0.22. (2) At what water velocity will fluidized beds of glass particles and metal particles have the same bed densities? The relation between fluidization velocity (uc), terminal velocity (ut) and bed...
130 kg of uniform spherical particles with a diameter of 60 mm and particle density 1500...
130 kg of uniform spherical particles with a diameter of 60 mm and particle density 1500 kg/m3 are fludised by water (density 1000 kg/m3, viscosity 0.001 Pa s) in a circular bed of cross-sectional area 0.2 m2. The single particle terminal velocity of the particles is 0.98 mm/s and the voidage at incipient fludisation is known to be 0.47. Determine: a. The minimum fludised velocity             b. height when the liquid flow rate is 2x10-5 m3/s.  
130 kg of uniform spherical particles with a diameter of 60 mm and particle density 1500...
130 kg of uniform spherical particles with a diameter of 60 mm and particle density 1500 kg/m3 are fludised by water (density 1000 kg/m3, viscosity 0.001 Pa s) in a circular bed of cross-sectional area 0.2 m2. The single particle terminal velocity of the particles is 0.98 mm/s and the voidage at incipient fludisation is known to be 0.47. Determine: The minimum fludised velocity and the bed height at incipient fludisation.                                The mean fludised bed voidage and height when...
In an industrial process, 20 mm diameter spherical steel ball bearings are heat-treated to improve their...
In an industrial process, 20 mm diameter spherical steel ball bearings are heat-treated to improve their durability. For application (1), the entire ball bearing needs to be heated evenly to 1000 K. For application (2), only the outer 1 mm of the ball is to be heated to a temperature in excess of 1000 K. The properties of the ball bearing are c = 0.5 kJ/kg*K; p = 7800 kg/m3; k = 50 W/m.K. At your facility, you have access...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT