Calculate the terminal velocity for a pollen grain falling through the air using the drag force equation. Assume the pollen grain has a diameter of 7 µm and a density of 0.3 g/cm3.
If this grain is released from the top of a tree (height 11 m), estimate the time it will take to fall to the ground. Hint: The pollen grain will reach its terminal velocity very quickly and will have this velocity for essentially the entire motion. Your answer will explain why pollen stays in the air for a very long time. (Assume the density of air to be 1.3 kg/m3.)


Calculate the terminal velocity for a pollen grain falling through the air using the drag force...
Find the terminal velocity (in m/s) of a spherical bacterium (diameter 1.73 µm) falling in water. You will first need to note that the drag force is equal to the weight at terminal velocity. Take the density of the bacterium to be 1.10 ✕ 103 kg/m3. (Assume the viscosity of water is 1.002 ✕ 10−3 kg/(m · s).)
1.) Find the terminal velocity (in m/s) of a spherical bacterium (diameter 1.94 µm) falling in water. You will first need to note that the drag force is equal to the weight at terminal velocity. Take the density of the bacterium to be 1.10 ✕ 103 kg/m3. (Assume the viscosity of water is 1.002 ✕ 10−3 kg/(m · s).
If a dense 20.0-kg object is falling in air at half its terminal velocity (drag force is proportional to the square of the object’s speed), what is the drag force on the object at this moment? a. 25 N b. 50 N c. 75 N d. 100 N e. 150 N
The drag force on falling box is described by FD=(1/2)ρACDv2, where ρ is the density of air, 1.2 kg/m3. The mass of the box is 12.0 g, and the effective area of the bottom of the box is 109 cm2. Assume a drag coefficient of 1.10 a) Determine the drag force on the box when it is falling at a speed of 1.21 m/s. b) The box will reach terminal speed when the drag force on it is equal to...
n Chapter 5 we look at drag due to air resistance for falling objects. Using the Dv form of dr discussed in class, write a program (or solve analytically) to determine how long (sec.) and how far m) a 150 gram ball whose radius is 3.5cm would fall before it reached 75% of its terminal velocity. Assume ball falls in air whose density is 1.21 kg/m3, has a drag coefficient C .3, cross-sectional area s just the disk a sphere...
5. In certain circumstances, we can model the velocity of a falling mass subject to air resistance as - dv m7 = mg – kv?, where v (t) is the velocity of the object, m is the mass of the object, g is acceleration due to gravity, and k is a constant of proportionality. Assume the positive direction is downward. (a) Solve this equation subect to the initial condition v (0) = vo. (b) What is the terminal velocity of...
N9M.2 and N9B.8
the ground WI time will pass before it returns to he g resistance.) 85 N9B.7 Estimate the terminal speed for a ping-pong bal so whose diameter is 1.5 in. and whose mass is 2.5 g. (For P a sphere, C is roughly 0.5.) N9B.8 A person's terminal speed in air is typically about 60 m/s. If so, what is the value for CA for a falling person? (Assume that m 60 kg.) N9 Modeling N9M.1 Estimate the...
Part 1 How fast do small water droplets of 0.23 um (23 x 108 m) diameter fall through the air under standard sea-level conditions? Assume the drops do not evaporate. Repeat the problem for standard conditions at 5000-m altitude. (a) For the condition that the droplets are falling at a constant velocity, what is the relation between the weight ofa drop W, the buoyancy force Fe, and the drag force F? (b) What is the expression for the weight of...
Lecture I1.3. Drag Force 267 26 percent of greenhouse gas emissions come from cars, with a typical passeng emitting about 4.7 metric tons of carbon dioxide per year. Assuming all of the rom overcoming air resistance (ignoring internal resistances and stopping/starting much would we need to reduce the 70 mph speed limits vehicle emissions are how to obtain a 20 percent cut in greenhouse er emissions from cars? 14. A small particle with a radius of 0.1 mm and drag...
(7%) Problem 4: A 66 kg and a 82 kg skydiver jump from an airplane at an altitude of 6000 m, both falling in the diving/headfirst position. Assume their surface area is 0.105 m and the drag coefficient is 0.70 Randomized Variables ,-66 kg m 82kg A-0105 m 50% Part (a) How long will it take for the first dner to reach the pound in seconds assuming the time to reach term na raloct Grade Summary Potential95 Submissio s man...