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Rotation

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

Question pertaining to a 3rd-class lever and angular velocity.

I need to show mathematically how two 3rd-class levers joined together in a series increase angular velocity versus using a single 3rd-class lever. For example, a football player kicking the ball from the tee. I need to compare when he kicks it with his kicking leg maintained in a straight condition, i.e. only his hip joint ro

Systems of units

1.A boeing 747 jet with 385 people cruising 39000 ft travels 280 yds on gallon of fuel. How many gallons will it need to travel 2000 km. a. How many meters does 200 km equal? b. How many meters does the plane travel per gallon of fuel? How many gallons will the plane need to travel 2000 km? 2. How may liters of water w

Rod/pin apparatus is featured.

Rigid rod OA is 2 ft long and rotated around fixed pt O. This rod is pinned at A to rigid connecting rod AB, 6 ft long, which in turn is pinned at B to piston C. This piston moves without friction along the y axis. The pins are also frictionless. Rod OA is positioned so that it is pi/3 radians above the x-axis and angular ve