Two objects, a cylinder and a hoop, roll down without slipping from the top of a frictional ramp at the same time. They are made of different materials, but both have the same mass and radius. Which one reaches the bottom first?

While working as an intern in a blacksmith's shop, you realize that the brake on the sharpening stone (a stone uniform disk) is no longer working. To stop the rotation at the end of the day, you put your knowledge of physics to good use and use a steel axe to stop the rotation. You press the steel axe against the stone using a radial force of 19.5 N. The stone is originally rotating at a rate of 85 revolutions per minute (out of the page), has a radius of 0.350 m, and a mass of 91.0 kg. Choose out of the page to be positive. a) Given a coefficient of kinetic friction between the stone and the axe equal to 0.20, what is the angular acceleration of the sharpening stone? b) What angular displacement did the stone turn through from its initial angular speed to when the stone stops rotating?

A solid ball (sphere) of mass 1 kg and radius 0.3 m is held at rest at the top of a ramp. There is enough friction so that the ball will roll down the ramp without slipping. The top of the ramp is 10 meters above the ground.What will the speed be of the ball just before it hits the bottom of the ramp?

Three small steel balls are connected by rigid, very light rods as shown in the figure. What is the moment of inertia if the object rotates about the x-axis? If we apply a force of 200. N to the most massive ball such that the object will rotate counterclockwise about the x-axis, what angular acceleration will result?

A student places a coin on a flat disk. The flat disk is allowed to rotate around an axis through its center. The angular velocity of the flat disk gradually increases. The coin initially rotates with the disk but eventually slides off the disk. Which of the following is the best explanation for the coin's behavior?   The kinetic friction was no longer large enough to provide the necessary angular acceleration   The kinetic friction was no longer large enough to provide the necessary centripetal acceleration   The static friction was no longer large enough to provide the necessary angular acceleration   The static friction was no longer large enough to provide the necessary centripetal acceleration

A vinyl record spins freely on a frinctionless turntable.  The mass of the record is 0.10 kg, the radius is 0.10 m, the rotational inertia is 5.0 x 10-4 kgm2 and it rotates with angular speed of 4.7 rad/s.  A 0.024 kg piece of clay falls on the edge of the record.  Determine the angular speed of the record right after the clay sticks to it. Use conservation of momentum.

1. In the figure below, block 1 has a mass of m1 = 450 g and block 2 has a mass of m2 = 500 g. The pulley, which is mounted on a horiztonal axle with negligible friction through its center, has a radius of 5.00 cm. When released from rest, block 2 falls without the cord slipping on the pulley, travelling 75.0 cm before it reaches a speed of 0.300 m/s. What is the rotational inertia of the pulley? m2

A small block on a frictionless, horizontal surface has a mass of 2.30x10-2 kg. It is attached to a massless cord passing through a hole in the surface (Figure 1). The block is originally revolving at a distance of 0.300 m from the hole with an angular speed of 2.87 rad/s. The cord is then pulled from below, shortening the radius of the circle in which the block revolves to 0.150 m. Model the block as a particle. Figure ▼ Express your answer with the appropriate units. AK = 2.8210-² Part D μA W = Submit Previous Answers Request Answer Submit 3 X Incorrect; Try Again; 3 attempts remaining → How much work was done in pulling the cord? Express your answer with the appropriate units. HÅ -0.0123 Provide Feedback J PHO ? J 0 PE ? Previous Answers Request Answer X Incorrect; Try Again; 5 attempts remaining Constants Next >