Torque
What are the two equations for torque?
Ia=FR
Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger angular displacement?
They have the same non-zero angular displacement.
What is the rotational kinetic energy formula?
K = (1/2)Iw2
What is the quantity used to measure an object's resistance to changes in rotational motion
Moment of Inertia
Average time per multiple choice questions on the AP exam.
What is 2 minutes?
A 2 kg disk is spinning at a rate of 12 rad/s. A force of 10 N is applied to the end of the wheel. What is the radius of the disc if the disc went to 20 rad/s in 1 second?
1.25 m
A boy and a girl are riding a merry-go-round which is turning at a constant rate. The boy is near the outer edge, while the girl is closer to the center. Who has the greater tangential acceleration?
Both have zero tangential acceleration.
What takes more energy to rotate a hoop or a disk?
Hoop
A dumbbell-shaped object is composed by two equal masses, m, connected by a rod of negligible mass and length r. If I1 is the moment of inertia of this object with respect to an axis passing through the center of the rod and perpendicular to it and I2 is the moment of inertia with respect to an axis passing through one of the masses we can say that
I1 < I2.
Average time per FRQ on the AP Physics exam?
What is 25 minutes?
How much force, applied to the rim, is needed to get a bicycle wheel (hoop) to spin at a rate of 100 rads/s from rest after 2 seconds? (r= 0.25 m, m= 4 kg)
50 N
An object starting from rest begins to rotate with constant angular acceleration α. In a time t the object rotates through an angle θ. Through what angle did the object rotate in the time t/3?
θ/9
A hoop with a mass of 2.75 kg is rolling without slipping along a horizontal surface with a speed of 4.50 m/s. What is the rotational energy of hoop?
27.8 J
A golf ball is a small solid sphere. A volleyball is a hollow sphere that is filled with air. A bicycle tire is a large rubber hoop-like object. If all three objects are released at the same instant at the top of an inclined plane and allowed to roll to the bottom, what is the order of finish?
Golf Ball, Volleyball, Bicycle Tire
Where is the headquarters of Nintendo? (city)
Kyoto
The engine of a BMW produces maximum torque of 245 N-m at a speed of 4200 rpm. What is the power this engine produces when it produces maximum torque?
108 kW
How long does it take a wheel that is rotating at 33.3 rpm to speed up to 78.0 rpm if it has an angular acceleration of 2.15 rad/s2?
2.18 s
A softball (mass = 185 g, radius = 4.85 cm, I = 1.74 x 10-4 kgm^2) rolls without slipping on a field with a linear speed of 18 m/s. What is the total kinetic energy of the ball?
42 J
A mass of 5.0 kg is attached to a string that is wound around a hollow cylinder of radius 10 cm. When released from rest the acceleration of the mass is 7.0 m/s2. What is the mass of the cylinder?
2.0 kg
The most-popular American football video game franchise is named after which individual?
John Madden
A CD disk has a radius of 6.0 cm and a mass of 16 g. Its moment of inertia is therefore 2.9 x 10-5 kg-m2. A certain CD player reaches it operating speed of 486 rpm in 0.40 s from rest. What constant torque did the motor produce?
3.7 * 10-3 N-m
Two gears are lined up. One has a radius of 10 cm and the other has a radius of 30 cm. If the 10 cm gear is driven by a motor at an angular speed of 60 rad/s, then how fast is the 30 cm gear moving?
20 rad/s
A hoop is rolling without slipping along a horizontal surface with a speed of 5.50 m/s when it starts up a ramp that makes an angle of 25.0° with the horizontal. What is the speed of the hoop after it has rolled 3.00 m up the ramp?
4.22 m/s
A boy and a girl are riding on a merry-go-round that is turning. The boy is twice as far as the girl from the merry-go-round's center. If the boy and girl are of equal mass, which statement is true about the boy's moment of inertia with respect to the axis of rotation?
His moment of inertia is 4 times the girl's
What classic video game did Tony Stark catch a member of S.H.I.E.L.D. playing in the first "Avengers" movie?
Galaga