2283

Physics Rotational Mechanics Level: High School

Circular Motion

What is the angular speed in rad/s of the second hand of a watch ?



2282

Physics Rotational Mechanics Level: High School

Circular Motion A bicycle travels 141 m along a circular track of radius 15 m . What is the angular displacement in radians of the bicycle from its starting position ?




2281

Physics Rotational Mechanics Level: High School

Conservation of Angular Momentum

A flat uniform circular disk (radius = 2.40 m , mass = 1.00 102 kg) is initially stationary . The disk is free to rotate in the horizontal plane about a frictionless axis perpendicular to the center of the disk . A 55.0 kg person standing 1.15 m from the axis , begins to run on the disk in a circular path and has a tangential speed of 2.00 m/s relative to the ground . Find the resulting angular speed of the disk (in rad/s) and describes the direction of the rotation



2280

Physics Rotational Mechanics Level: High School

Conservation of Angular Momentum

A woman stands at the center of a platform . The women and the platform rotate with an angular speed of 5.00 rad/s . Friction is negligible . Her arms are outstretched , and she is holding a dumbbell in each hand . In this position the total moment of inertia of the rotating system (platform women, and dumbbells) is 5.40 kgm2 . By pulling in her arms . she reduces the moment of inertia to 60 kgm2 . Find her new angular speed .



2279

Physics Rotational Mechanics Level: High School

Conservation of Angular Momentum

A bowling ball encounters a 0.76 m vertical rise on the way back to the ball rack . Ignore frictional losses and assume that the mass of the ball is distributed uniformly. If the translational speed of the ball is 5.10 m/s at the bottom of the rise , find the translational speed at the top .



2278

Physics Rotational Mechanics Level: High School

Conservation of Energy

A helicopter has two blades , each of which has a mass of 240 kg can be approximately as a thin rod of length R = 8.1 m .



2277

Physics Rotational Mechanics Level: High School

Conservation of Energy

A thin uniform rod is initially positioned in the vertical direction , with its lower end attached to a frictionless axis that is mounted on the floor . The rod has a length of 2.50 m and is allowed to fall , starting from rest . Find the tangential speed of the free end of the rod , just before the rod hits the floor after rotating through 90 degrees .



2276

Physics Rotational Mechanics Level: High School

Rotational Equilibriums

A women who weighs 4.80 102 N is leaning against a smooth vertical wall .

a) Find the force FN (directed perpendicular to the wall) exerted on her shoulder by the wall .

b) Find the horizontal component of the force exerted on her shoes by the ground .

c) Find the vertical component of the force exerted on her shoes by the ground

.



2275

Physics Rotational Mechanics Level: High School

Equilibrium of moments

A uniform plank of length 4.6 m and weight 216 N rests horizontally on two supports , with 1.1 m of the plank hanging over the right support . To what distance x can a person who weighs 452 N walk on the overhanging part of the plank before it just begins to tip ?



2274

Physics Rotational Mechanics Level: High School

In San Francisco a very simple technique is used to turn around a cable car when it reaches the end of its route . The car rolls onto a turntable , which can rotate about a vertical axis through its center . Then , two people push perpendicularly on the car , one at each end . The turntable is rotated one-half of a revolution to turn the car around . If the length of the car is 9.00 m and each person pushes with a 170 N force , what is the magnitude of the torque applied to the car ?



2273

Physics Rotational Mechanics Level: High School

Circular Motion

Two people start at the same place and walk around a circular lake in opposite directions . One has and angular speed of 1.2 10-3 rad/s , while the other has an angular speed of 3.5 10-3 rad/s . How long will it be before they meet ?



2272

Physics Rotational Mechanics Level: High School

Circular Motion

Suppose you are riding a stationary exercise bicycle , and the electronic meter indicates that the wheel is rotating at 8.2 rad/s . The wheel has a radius of 0.45m . If you ride the bike for 2070 s , how far would you have gone if he bike could move ?



2271

Physics Rotational Mechanics Level: High School

Circular Motion

An automobile tire has a radius of 0.280 m , and its center moves forward with a linear speed of v = 19.0 m/s .

a) Determine the angular speed of the wheel . (Assume that there is no slipping of the surfaces in contact during the rolling motion )

b) Relative to the axle what is the tangential speed of a point located 0.175 m from the axle ?




2270

Physics Rotational Mechanics Level: High School

Circular Motion

An auto race is held on a circular track . A car completes one lap in a time of 19.4 s , with an average tangential speed of 40.1 m/s . Find the following .

a) The average angular speed .

b) The radius of the track .




2269

Physics Rotational Mechanics Level: High School

Equations of Rotational Motion

The angular speed of the rotor in a centrifuge increases from 340 to 1340 rad/s in a time of 5.00 s .

a) Obtain the angle through which the rotor turns .

b) What is the magnitude of the angular acceleration ?


Displaying 331-345 of 497 results.