Physics Rotational Mechanics Level: High School
A bicycle has wheels of radius 0.33 m . Each wheel has a rotational inertia of 0.081 kgm^2 about its axle . The total mass of the bicycle including the wheels and the rider is 71 kg . When coasting at constant speed , what fraction of the total kinetic energy of the bicycle (including rider) is the rotational kinetic energy of the wheels ?Physics Rotational Mechanics Level: High School
Rotational Equilibrium
A 4.0 m wood plank of mass 100.0 kg is nailed to two supporting “horses” at each end . Two painters stand on the plank as shown in the diagram at “click here” . Assume the center of gravity is in the middle of the plank . Find the force acting down on the left and right “horses” .Physics Rotational Mechanics Level: High School
Torque
The man in the diagram which is shown at “click here” is trying to bend the tree . He ties a rope to the tree at a point 5.6 m above the ground and pulls with a force of 65 N . He stands 4.0 m from the base of the tree . Find the bending torque on the tree . (Hint : use trig to get some angle ) .Physics Rotational Mechanics Level: High School
What occurs when a torque is applied to an object that is free to rotate ?Physics Rotational Mechanics Level: High School
What’s the magnitude of the torque if a door is turned with 20 . N force applied 0.70 m from the door’s hinges ?Physics Rotational Mechanics Level: High School
A solid disk of steel has a diameter of 0.600 m and a mass of 234 kg rolls horizontally without slipping at 1.5 m /s . Find its KE (total) in J , using the combined or alternative equation p.298 (eq. 10-20) .Physics Rotational Mechanics Level: High School
A 250.g basketball of diameter 30.0 cm rolls slowly along the floor at 20.0 cm/s . Solve separately for its KE (linear) and KE (rotation) , both in J .Physics Rotational Mechanics Level: High School
Use the data on the rear inside cover of your text to calculate the KE (rotation) of the earth on its axis . (Hint : get omega in radians / s knowing that earth rotates once in 24 hours )Physics Rotational Mechanics Level: High School
Conservation of Angular Momentum
A skater spins at 6.0s^-1 with one leg and both arms stretched from her body so her effective I is 90 kg*m^2 . What will be her angular velocity when she pulls in her leg and arms to her sides making her effective I only 40. Kg*m^2 ? ?Physics Rotational Mechanics Level: High School
What’s the angular momentum of a solid square plate that measures 20.0 cm on each side are rotates at 25 radians / s around an axis perpendicular to the plane of the plate ?Physics Rotational Mechanics Level: High School
What’s the angular momentum of a 0.500 kg ball moving in a circle at a speed of 4.0 m/s at the end of a 1.2 m cord ?Physics Rotational Mechanics Level: High School
Moment of Inertia
Calculate I for the system which is shown at “click here” . Ignore the mass of the rods .Physics Rotational Mechanics Level: High School
A 5.00 kg ball is swung at the end of a 1.25 m chain with an omega of 2.0 s^-1 . Find the ball’sa) V (m/s)
b) KE using ½ mV^2
c) I , its moment of inertia
d) KE using its I
e) Fc , the centripetal force exerted by the athlete
Physics Rotational Mechanics Level: High School
A bikes wheel has a diameter of 70.0 cm . If it is rolling at 4.00 revolutions / sec . Finda) the forward velocity of the bike (linear motion )
b) the velocity of a point at the top of the tire .
c) the velocity of a point at the bottom of the tire where it touches the rod .
Physics Rotational Mechanics Level: High School
A car tire of radius 45 cm turns at a constant 14 rad/s . For a point on the edge calculate .a) the tangential V
b) the tangential “a”
c) the centripetal “a”