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Tangential Speed and Acceleration

A helicopter blade has an angular speed of 6.50 rev/s and an angular acceleration of 1.30 rev/s^2. Find the magnitudes of the tangential speed and acceleration for a point (a) 3.00m from the center of rotation and (b) a point on the blade 6.70 m from the center of rotation.

What is the force needed for circular motion?

A spring scale on a rotating platform indicates that the horizontal force on a 0.452 kg mass is 1.34N when the mass is 2.37m from the axis of rotation. How long does it take for the platform to make on revolution?

Pressure in a Centrifuge

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Please see attached for actual problem.

Angular Velocity and Rotational Energy

A disk of radius .3 meters and mass of .5kg is held over another disk of radius .5 meters and mass 1 kg which is rotating in a horizontal plane at a rate of 15.92 rev/sec. The top disk is released and drops onto the bottom disk (centers align). a) What is the final angular velocity (in rev/sec) of the two disks? b) What was

Center of percussion-center of mass

A baseball bat rests on a frictionless, horizontal surface. The bat a length of 0.900m, a mass of 0.800 kg, and its center of mass is 0.600m from the handle end of the bat. ThE MOMENT OF INERTIA OF THE BAT ABOUT ITS CENTER OF MASS IS 0.0530kg*m^2 The impact applies an impulse : J= integral from t2 to t1 of F*dt. at a po

Rotation of rigids body

Can you think of a body that has the same moment of inertia for all possible axis? If so, give an example, and if not, explain why it is not possible.

Angular Speed - Rotational Kinematics

Learning Goal: To understand the meaning of the variables that appear in the equations for rotational kinematics with constant angular acceleration. Rotational motion with a constant nonzero acceleration is not uncommon in the world around us. For instance, many machines have spinning parts. When the machine is turned on or o

Calculating the Resultant Force of a Ride

Question: In an amusement park ride called The Roundup, passengers stand inside a 19.0m diameter rotating ring. After the ring has acquired sufficient speed, it tilts into a vertical plane, as shown in the figure (see attachment). A. Suppose the ring rotates once every 4.70s. If a rider's mass is 52.0kg, with how much force

Electromagnetics Problems

1. The flux in a single-loop coil of area 37 cm^2 steadily changes from 6.5 x 10^-3 T to 9.3 x 10^-3 T in 0.50s. What emf is induced in the coil? 2. A wire coil of 25 turns has a cross-sectional area of 10 cm^2. The coil is placed in a uniform field of large magnet with B=0.20 T. The coil is suddenly rotated 90 degrees from a

Centripetal Force & Work

Does a centripetal force that acts on an object rotating in a circular path do work on an object? What is your explanation, and what evidence can you cite to support your answer?

Weight differences in scale in Mexico versus Alaska

Please answer the question using these types of ideas. It is a conceptual question that needs a detailed explanation: If you should buy a quantity of gold in Mexico and weigh it careully on a spring balance, would the same quantity of gold weigh more, less, or the same if weighed on the same spring balance in Alaska? Defend you


A helicopter has 3 blades, each of them are 5.20m long and has a mass of 220kg.(each blade has a mass of 220kg, not the sum of the 3) The rotor is rotating at 385 rev/min. a)What is the rotational inertia of the rotor assembly about the axis of rotation? (Each blade can be considered to be a thin rod rotated about one end.)

Newton's 2nd Law for Rotation

Problem 1 A wheel of radius 0.20 meters is mounted on a frictionless horizontal axis. The rotational inertia of the wheel about the axis is 0.050 kgm^2. A massless cord wrapped around the wheel is attached to a 2.0 kg block that slides on a horizontal frictionless surface. If a horizontal force of magnitude P=3.0 N is applie

Motion at a Fixed Point

Please see attachments for my question about a rotating radar antenna's angular velocity. Please use i, j and k vector coordinates to solve.

Calculating Acceleration: Instant Center of Rotation in Plane Motion

Question: The motion of the 3-in.-radius cylinder is controlled by the cord shown (please refer to attachment for diagram). Knowing that end E of the cord has a velocity of 12 in./s and an acceleration of 19.2 in./s^2, both directed upward, determine the acceleration (a) of point A, (b) of point B.

KE/rotational motion

"A car is designed to get its energy from a rotating flywheel with a radius of 2.20 m and a mass of 499 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 5120 revolutions per minute. Find the kinetic energy stored in the flywheel."

Final angular speed of system

A solid, horizontal cylinder of mass 10.4 kg and radius 1.13 m rotates with an angular speed of 6.81 rad/s about a fixed vertical axis through its center. A 0.251 kg piece of putty is dropped vertically onto the cylinder at a point 0.864 m from the center of rotation, and sticks to the cylinder. Determine the final angular speed

Moment of inertia of a 14.0 kg sphere of radius 0.645 m

"Calculate the moment of inertia of a 14.0 kg sphere of radius 0.645 m when the axis of rotation is through its center." I thought the equation was simply: I = mr^2 = (14.0)(0.645)2 = 5.82 kg*m^s but that's not the answer.

Rotational Motion

A bicycle with 56.0 cm diameter tires travels 6.40 km. How many revolutions do the wheels make?

What is the speed of the train around a curve?

A train traveling at a constant speed rounds a curve of radius 286 m. A chandelier suspended from the ceiling swings out to an angle of 15.7 degrees throughout the turn. What is the speed of the train?

Physics: A child sits on a rotating merry-go-round

A child sits on a rotating merry-go-round, 2.1 meters from its center. If the speed of the child is 1.0 m/s, what is the minimum coefficient of static friction between the child and the merry go round that will prevent the child from slipping.

Determine the principal stresses and the maximum shear stress in a spindle

See attached diagram. The pedal crank of a racing cycle is to be analysed to assess whether the stresses are excessive. Pedal loads can reach 500N (causing bending) and produce a torque of 100Nm. The location of load application alternates each half rotation of the spindle (from locations A to F) as shown in the attached di