The Earth's atmosphere normally contains a large number of very small particles, for instance water droplets and carbon soot, generally called aerosols. Consider a spherical water droplet in still air falling under gravity. If the radius of the droplet is 5 microns, what is its maximum speed of fall (the terminal velocity)? The density of water is pw = 1000 kg/m³ and the dynamic viscosity of air at 20°C is 1.8 x 10 kg/m s.

The Earth's atmosphere normally contains a large number of very small particles, for instance water droplets and carbon soot, generally called aerosols. Consider a spherical water droplet in still air falling under gravity. If the radius of the droplet is 5 microns, what is its maximum speed of fall (the terminal velocity)? The density of water is pw = 1000 kg/m³ and the dynamic viscosity of air at 20°C is 1.8 x 10 kg/m s.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

A person is in a closed room (a racquetball court) with V = 453 m3 hitting a ball (m = 42.0 g) around at random without any pauses. The average kinetic energy of the ball is 2.30 J. (a) What is the average value of vx 2 ? Does it matter which direction you take to be x? (b) Applying the methods of this chapter, find the average pressure on the walls? (c) Aside from the presence of only one “molecule” in this problem, what is the main assumption in Pressure, Temperature, and RMS Speed that does not apply here?
In a 30.0-s interval, 500 hailstones strike a glass window of area 0.600 m2 at an angle of 45.0° to the window surface. Each hailstone has a mass of 5.00 g and a speed of 8.00 m/s. Assuming the collisions are elastic, find (a) the average force and (b) the average pressure on the window during this interval.
Two moles of an ideal gas is placed in a container whose volume is 3.1 x 10-3 m3. The absolute pressure of the gas is 3.5 x 105 Pa. What is the average translational kinetic energy of a molecule of the gas?
Bacteria have a density that is about the same as water. Their average velocity is 10^-3 m/s. A bacterium with a radius of 1 um should have a diffusion coefficient of about 2.2x10^-13 m^2/s. (a) Find the random-walk step size (b) How long does it take for an average walk to reach 1 mm in seconds and days? Note that we are considering the diffusion away from the starting point and are calculating the distance through three dimensions. Show your work
The density of water at 0°C is very nearly 1000 kg/m3 (it is actually 999.84 kg/m3), whereas the density of ice at 0°C is 917 kg/m3. The bulk modulus of ice is 2.20 × 109 Pa. a. Calculate the pressure, in pascals, necessary to keep freezing water from expanding, neglecting the effect such a large pressure would have on the freezing point. (This problem gives you only an indication of how large the forces associated with freezing water might be.)
In one observation, the column in a mercury barometer has a measured height h of 740.35 mm.The temperature is 5.0 C, at which temperature the density of mercury r is 1.3608 * 10^4 kg/m3.The free-fall acceleration g at the site of the barom- eter is 9.7835 m/s2.What is the atmospheric pressure at that site in pascals and in torr (which is the common unit for barometer readings)?
VRMS-1 Consider a container of Argon gas at a temperature of 25.0 °C. The mass of an Argon atom is 39.96 AMU, where 1 AMU = 1.66×10-27 kg. (a) What is the average kinetic energy per Argon atom, in Joules (J)? (b) What is the RMS average speed of the Argon atoms, in meters per second (m/s)? (c) What would the temperature of the gas have to be for the RMS average speed to 275 m/s? Give your answer in degrees Celsius (°C).
Consider a spherical ash particle of diameter 65 µm, falling from a volcano at a high elevation in air whose temperature is −50°C and whose pressure is 55 kPa. The density of air is 0.8588 kg/m3 and its viscosity is 1.474 × 10−5 kg/m⋅s. The density of the particle is 1240 kg/m3. The drag force on a sphere in creeping flow is given by FD = 3??VD. The terminal velocity of this particle at this altitude is (a) 0.096 m/s (b) 0.123 m/s (c) 0.194 m/s (d ) 0.225 m/s (e) 0.276 m/s
Part A - A cube of volume 3.0 ×10-3 m3 (3.0 L) is placed on a scale in air. The scale reads 267 N. What is the material? Answers: Copper, ρ = 8.9 × 103 kg/m3 Aluminum, ρ = 2.7 × 103 kg/m3 Gold, ρ = 19 × 103 kg/m3 Lead, ρ = 11 × 103 kg/m3 Part B - An aluminum block of volume 200 × 10-6 m3 is held by a string at rest in oil as shown. ρAL = 2700 kg/m3, ρoil = 900 kg/m3, and g = 10 m/s2. Now the same block is placed in water, still completely submerged. Water is more dense than oil. The net force on the block will ______. Answers: decrease increase stay the same Part C - Now the same block is placed in water, still completely submerged. Water is more dense than oil. The buoyant force on the block will ______. Answers: stay the same decrease increase Part D - Now the same block is placed in water, still…