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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

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?


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

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

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?

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

Angular motion with constant acceleration of a ceiling fan

A ceiling fan has one red blade. Initially rotating in a counterclockwise (positive direction) with angular velocity Wo= +30 radians per second. SEE THE ATTACHMENT FOR A PICTURE WITH KNOWN DATA. At that instant, when the red blade makes an angle Qo= +1.4 radians from the +x axis, the current is reversed and a timer is started

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 and Pin Apparatus: Friction, Acceleration, and Velocity

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