We often think of friction and air resistance as forces that we want to minimize because they can hinder the motion of an object. But they are not always undesirable, and in fact, can be an essential element in a machine or process. Identify one or two applications that depend on friction and air resistance. Explain how friction or air resistance works in those situations and what would happen if there were no friction or air resistance. Your initial post should be 75-150 words in length and is due on Sunday.

We often think of friction and air resistance as forces that we want to minimize because they can hinder the motion of an object. But they are not always undesirable, and in fact, can be an essential element in a machine or process. Identify one or two applications that depend on friction and air resistance. Explain how friction or air resistance works in those situations and what would happen if there were no friction or air resistance. Your initial post should be 75-150 words in length and is due on Sunday.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter7: Work And Kinetic Energy

Section: Chapter Questions

Problem 75P: (a) How long would it take a 1.50105kg airplane with engines that produce 100 MW of power to reach a...

See similar textbooks

Similar questions

Please refer to the picture with the formulas needed to solve this problem. Please only use the formulas, constants, and units from the picture given. To simulate various processes on the surface on Mars, a labratory uses an Atwood machine to simulate Martian gravitational acceleration. An Atwood machine is a setup involving two objects connected by a string that runs over a pulley. For this problem, assume that the string and pulley are ideally frictionless, massless, and inextensible. One object is a bucket holding the subject of the labratory's experiment, which in total has a mass mb. The other object is a counterweight, whose mass Mc must be properly selected to ensure that the experiement's downward acceleration matches that of Martian gravity, gM. Part 1) The experimenter want the bucket to be accelerated as if it were being dropped near the surface of Mars. Which mass must be bigger, Mb (the bucket) or Mc (the counterweight)? How does the acceleration of the bucket compare…
Please refer to the picture with the formulas needed to solve this problem. Please only use the formulas, constants, and units from the picture given. To simulate various processes on the surface on Mars, a labratory uses an Atwood machine to simulate Martian gravitational acceleration. An Atwood machine is a setup involving two objects connected by a string that runs over a pulley. For this problem, assume that the string and pulley are ideally frictionless, massless, and inextensible. One object is a bucket holding the subject of the labratory's experiment, which in total has a mass mb. The other object is a counterweight, whose mass Mc must be properly selected to ensure that the experiement's downward acceleration matches that of Martian gravity, gM. Part 1) The experimenter want the bucket to be accelerated as if it were being dropped near the surface of Mars. Which mass must be bigger, Mb (the bucket) or Mc (the counterweight)? How does the acceleration of the bucket compare…
A roller-coaster car shown in the figure is pulled up to point 1 where it is released from rest. (Figure 1) Part A Assuming no friction, calculate the speed at point 2. Express your answer to two significant figures and include the appropriate units. HA ? Value Units Submit Request Answer Part B Assuming no friction, calculate the speed at point 3. Express your answer to two significant figures and include the appropriate units. Figure 1 of 1 HA Value Units V3 = 32 m 26 m 14 m Submit Request Answer Part C P Type here to search N 立
February 3, 2009, was a very snowy day along Interstate 69 just outside of Indianapolis, Indiana. As a result of the slippery conditions and low visibility (50 yards or less), there was an enormous accident involving approximately 30 vehicles, including cars, tractor-trailers, and even a fire truck. Many witnesses said that people were driving too fast for the conditions and were too close together. In this problem, we explore two rules of thumb for driving in such conditions. The first is to drive at a speed that is half of what it would be in ideal conditions. The other is the 8-second rule: Watch the vehicle in front of you as it passes some object such as a street sign, and you should pass that same object 8 seconds later. On a dry road, the 8-second rule is replaced by a 3-second rule. a. Assume vehicles on a slippery interstate highway follow both rules. What is the distance between the vehicles? b. If a driver followed the first rule of thumb, driving at a lower speed, but used the 3-second rule instead of the 8-second rule, what is the distance between the vehicles? How does that distance compare with the visibility on the day of the accident? c. Suppose drivers do not follow either rule of thumb for slippery conditions. What is the distance between vehicles? How does that distance compare with the visibility on that day? d. Suppose a driver was not obeying either rule of thumb when she sees a tractor-trailer that stopped on the highway. She presses on her brakes, locking the wheels, and her car crashes into the truck. Estimate the magnitude of the impulse exerted on her car. e. Estimate the impulse on the car in part (d) had the driver followed both rules of thumb for slippery conditions instead of ignoring them.
A 150-g baseball is dropped from a tree 15.0 m above the ground. a.)With what speed would it hit the ground if air resistance could be ignored? Express your answer to three significant figures and include the appropriate units. b.)If it actually hits the ground with a speed of 8.00 m/s, what is the magnitude of the average force of air resistance exerted on it? Express your answer to three significant figures and include the appropriate units.
Worksheets 4. Examine the diagram of an air powered car. At what point will the car stop moving?
An E. coli bacterium can be modeled as a 0.50-um-diameter sphere that has the density of water. Rotating flagella propel a bacterium through 40° C water with a force of 75 EN, where 1 fN=1 femtonewton = 10-15 N. Part A What is the bacterium's speed in μm/s? Express your answer in micrometers per second. ΨΕ ΑΣΦ 7.16 107 DMC Submit Previous Answers Request Answer X Incorrect; Try Again ? um/s
A roller-coaster car shown in the figure below is pulled up to point 1 where it is released from rest. Take y = 36 m. (Figure 1) Figure 2 4 A 26 m 14m 1 of 1 Part A Assuming no friction, calculate the speed at point 2. Express your answer to two significant figures and include the appropriate units. v2 = Submit Part B v3 = Submit Part C 123+ v4= Value Calculate the speed at point 3. Express your answer to two significant figures and include the appropriate units. Submit 123+ Value S Request Answer C = ? 123+ Provide Feedback Units Value Calculate the speed at point 4. Express your answer to two significant figures and include the appropriate units. (>= ? Request Answer Units = ? Units Request Answer
A water slide is connected so that a swimmer, starting from rest at the top of the slide, leaves the end of the slide travelling horizontally. one person hits the water 6m from the end of the slide in a time 0.4 seconds after leaving the slide. ignoring friction and air resistance, find the height H. b) how does the answer change if the swimmer leves the end at an angle of 10 degrees above the horizontal?
Review I Constants I P A car has a mass of 1500 kg. If the driver applies the brakes while on a gravel road, the maximum friction force that the tires can provide without skidding is about 7000 N. Part A If the car is moving at 26 m/s, what is the shortest distance in which the car can stop safely? Express your answer to two significant figures and Include the approprlate units. HA Az = Value Units Submit Previous Answers Request Answer X Incorrect; Try Again; 2 attempts remaining Provide Feedback FEB 13 J O stvN
A projectile of mass 0.75 kg is shot straight up into the air with an initial speed of 20 m/s. a. How high would it go if there were no air resistance? b. If the projectile rises to a maximum height of 12 m, determine the magnitude of the average force due to air resistance.
When the 150-lb skier is at point A he has a speed of 5 ft/s. When the skier reaches point B on the smooth slope, the slope follows the cosine curve shown in (Figure 1). Suppose that y(x)=75cos(π/100x). Neglect friction and air resistance. Part A: Determine the skier's speed when he reaches point B on the smooth slope. Express your answer in feet per second to three significant figures. Part B: Also, what is the normal force on the skier's skis at BB? Express your answer in pounds to three significant figures. Part C: What is the skier's rate of increase in speed at BB? Express your answer in feet per second squared to three significant figures.