test 3

Mark bought a pizza of a radius of 0.5 m. A fly lands on the pizza and walks around the edge for a distance of 80 cm. What is the angular displacement of the fly?

1. 5r2 and I have two disks. I know that disk A has a mass per unit area o given by o = disk B has o = 3r3. Each disk has radius 10cm. I have a slope at angle 45 degrees to the horizontal that is 2 m long. I time with a stop watch how long it takes the disks to roll down the slope without slipping. (Assuming that the disk's are let go with zero velocity at the top of the slope). a) Calculate the mass of each disk. [4 marks]

A typical road bike wheel has a diameter of 70 cm including the tire. In a time trial, when a cyclist is racing along at 12 m/s:a. How fast is a point at the top of the tire moving?b. How fast, in rpm, are the wheels spinning?

The angular velocity vs. time for a car radiator fan is shown below. What is the angle (in rad) through which the fan blades rotate in the first 8 seconds? 400 300 200 100 0 1 4 6. 7 8. Time (s) Rev/min 2.

A car tire is 61.0 cm in diameter. The car is traveling at a speed of 24.0 m/s. What is the tire's rotation frequency, in rpm? What is the speed of a point at the top edge of the tire? What is the speed of a point at the bottom edge of the tire?

An 8.79cm diameter floppy disk rotates at its fastest at 470 rpm.  Part D: What is the angular velocity at the center of the disk?  Part E: If the disk took 3.2 sec to spin up to 470 rpm from rest, what was the average angular acceleration? How many revolutions did the disk complete within this time? What is the net displacement?  Part F: If you turn off the floppy disk drive and the disk comes to a stop in 6.7 s, what is the average angular acceleration for this period of motion?

. The last of the Babylon space stations, Babylon 5, is a cylinder of radius 420 m and mass 9.1 x 1012 kg. To simulate gravity the station spins around the axis of the cylinder. A person at the rim of the station experiences a weight 1.5 times the weight they would have on Earth's surface. What is the rotational rate of Babylon 5 in rpm? Explain including free body diagrams.

Q2: Consider a cylindrical container that has water in it. The cylinder rotates about its axis at an angular speed of w. Upon rotation, the level of water will not remain flat; it will be curved such that it has an increasingly higher level as one moves away from the centre towards the walls of the cylinder. Consider a coordinate system that is fixed at the cylinder and rotates with at the same angular velocity. Take the z' axis to be aligned with the axis of the cylinder such that the angular velocity points along the +z' direction. The x'y plane is, hence, parallel to the cylinder base. Place your coordinate system such that the lowest point on the water surface is at the origin. Solve the following questions: (a) Consider a point mass m that is located at the surface of the water at the coordinates (x', 0, z'). Draw a free body diagram of the mass indicating the directions of the weight, the "normal" force' (FN) from the rest of the water, and all inertial (fictitious) forces. (b)…

P.nil

3. A new discovered asteroid were observed by astrophysicist. It is said to be moving along a circular path of diameter 600 km. If it is revolving with an angular velocity of (3t2) rad/s, where t is in seconds, find the magnitude of the asteroid's velocity and acceleration when 0 = 30°. Note that 0 = 0° when t=0.

A typical hard disk in a desktop computer is a uniformly solid, 400 gram disk 3.5 inches in diameter, and takes 70 milliseconds to spin from rest up to a frequency of 7200 revolutions per minute (r.p.m.). Problem 2.1. What is the period of the disk in seconds when it’s at its final spinning rate? Problem 2.2. What is its angular speed in rad/s when it’s at its final spinning rate? Problem 2.3. Assuming it is constant throughout this spin-up process, what is the angular acceleration of the disk in rad/s2?

An optical disk drive in your computer is spinning at 10,000 rpm (1045 rad/s).  It decelerates to a rest in 0.42 s. a. Find the angular acceleration. b. If the disk is 0.115 m in diameter, what is the magnitude of the tangential acceleration at a point 1/2 of the way out from the center?

A ferris wheel begins at rest. During the first part of the journey, the ferris wheel accelerates through 4 rotations at a rate of 0.0500 rad/s2. During the second part of the journey, the ferris wheel then remains at its top speed for 14 rotations. Finally, during the third part of the journey, the ferris wheel slows down to rest over 3 rotations. What is the ferris wheel's top angular speed? How long does it take for the ferris wheel to accelerate from rest up to its top speed? How long the ferris wheel remain at its top speed for? How long does it take for the ferris wheel to slow down from top speed to rest?

In 2010, the Sikorsky's X2 helicopter became the world's fastest helicopter, flying at 249 miles per hour. When flying over 230 mph, the rotor speed is reduced from 446 to 360 RPM to keep tip speed below Mach 0.9. If each one of the six rotor blades is about 4.02 m long, how fast is the blade tip actually moving when the rotational speed is 360 RPM?

A bicycle with 0.80-m-diameter tires is coasting on a level road at 5.6 m/s. A small blue dot has been painted on the tread of the rear tire.a. What is the angular speed of the tires?b. What is the speed of the blue dot when it is 0.80 m above the road?c. What is the speed of the blue dot when it is 0.40 m above the road?

A circular plate is in the vertical position rotatable about a horizontal axis located on the edge of the plate. We raise the plate to the highest position and lower it. At what angular velocity does it move through the lowest point? Radius of the plate is 45 cm.

A. A large rotating cylinder uniformly increases in angular speed from rest to 0.170 rev/s in 28.0 s. What is its angular acceleration in radians per second per second?

There is a clever kitchen gadget for drying lettuce leaves after you wash them. It consists of a cylindrical container mounted so that it can be rotated about its axis by turning a hand crank. The outer wall of the cylinder is perforated with small holes. You put the wet leaves in the container and turn the crank to spin off the water. The radius of the container is 14.9 cm. When the cylinder is rotating at 1.28 revolutions per second, what is the magnitude of the centripetal acceleration at the outer wall?  _____ m/s^2

A 17 g audio compact disk has a diameter of 12 cm. The disk spins under a laser that reads encoded data. The first track to be read is 2.3 cm from the axis; as the disk plays, the laser scans tracks farther and farther from the center. The part of the disk directly under the read head moves at a constant 1.2 m/s. a. When a disk is inserted, it takes 2.4 s to spin up from rest. What is the torque of the motor?b. As the disk plays, how does the angular speed change?

A ferris wheel begins at rest. During the first part of the journey, the ferris wheel accelerates through 4 rotations at a rate of 0.0420 rad/s². During the second part of the journey, the ferris wheel then remains at its top speed for 18 rotations. Finally, during the third part of the journey, the ferris wheel slows down to rest over 5 rotations. What is the ferris wheel's top angular speed? unit How long does it take for the ferris wheel to accelerate from rest up to its top speed? unit How long the ferris wheel remain at its top speed for? unit How long does it take for the ferris wheel to slow down from top speed to rest? unit How long does the ferris wheel ride take in total, from start to finish? unit

A Ferris wheel rotates 5 times each minute. The passenger sit in seats that are 20 feet from the center of the wheel. What is the angular velocity of the wheel in radians per minute?

Two bugs, Buzz and Crunchy, are siting on a spinning disk. Buzz is sitting halfway and Crunchy is sitting at the outer edge as shown. The radius of the disk is 1.6 m and the disk is rotating with an angular speed of 33 rpm. What is Crunchy's speed, in m/s?

A 90 cm long rod rotates around the horizontal axis at one end. We raise the rod to the highest position and let it fall. With what angular speed is it moving at the lowest point?

A computer drive disk with a radius of 0.065 m is turned on starting from rest with a constant angular acceleration. It takes 2.50 s to complete 10 revolutions.  How long does it take to complete one revolution? What is the translational (linear) displacement of the rim of the computer drive disk after 10 revolutions?

A car is on a race track of radius 1200 feet. The car begins moving at 118 ft/s, but accelerates at 12.2 ft/s2 up to its top speed, traveling 2510 feet to do so. What is the angular displacement, angular acceleration and initial angular speed of the car about the track?

A 30.5-cm-radius tire on a moving car turns through 3π rad in 0.25 s. What is the speed of the car in kilometers per hour?

Ä bus starts from rest and travels with a constant acceleration of 1.6 m/s for 10.3 s. What is the magnitude of the cars displacement (in meters) at the end of the 10.3 s? B. A drum is rotating initially at 20 rad/s and undergoes a constant angular acceleration of 0.54 rad/s for 15 s. What is the angular displacement?

A CD originally spinning at 636.9 revolution per minute slows down uniformly until it comes to a full stop after 9.2 s. What is the magnitude of the angular acceleration of the disk during this period? Express answer in rad/s? and in 2 decimal places.