A uniform disk of mass 381 kg and radius 0.18 m is mounted on frictionless bearings so it can rotate freely around a vertical axis through its center (see the following figure). A cord is wrapped around he rim of the disk and pulled with a force of 10 N. 10 N (a) How much work (in J) has the force done at the instant the disk has completed two revolutions, starting from rest? (b) Determine the torque due to the force. (Enter the magnitude in N. m.) N.m Calculate the work (in J) done by this torque at the instant the disk has completed two revolutions. (c) What is the angular velocity (in rad/s) at that instant? (Enter the magnitude.) rad/s

A point on the rim of a 0.30 m radius rotating wheel has a tangential speed of 5.0 m/s. What is the tangential speed of a point 0.20 m from the center of the same wheel?

(a) Without the wheels, a bicycle frame has a mass of 8.19 kg. Each of the wheels can be roughly modeled as a uniform solid disk with a mass of 0.820 kg and a radius of 0.343 m. Find the kinetic energy of the whole bicycle when it is moving forward at 2.90 m/s. 37.88 Your response differs from the correct answer by more than 10%. Double check your calculations. J (b) Before the invention of a wheel turning on an axle, ancient people moved heavy loads by placing rollers under them. (Modern people use rollers, too. Any hardware store will sell you a roller bearing for a lazy susan.) A stone block of mass 819 kg moves forward at 0.290 m/s, supported by two uniform cylindrical tree trunks, each of mass 82.0 kg and radius 0.343 m. No slipping occurs between the block and the rollers or between the rollers and the ground. Find the total kinetic energy of the moving objects.

A 270-g mass hangs from a string that is wrapped around a pulley, as shown in the figure. The pulley is suspended in such a way that it can rotate freely. When the mass is released, it accelerates toward the floor as the string unwinds. Model the pulley as a uniform solid cylinder of mass 1.00 kg and radius 5.00 cm. Assume that the thread has negligible mass and does not slip or stretch as it unwinds. Determine the magnitude a of the pulley's angular acceleration. 344 rad/s? Incorrect Determine the magnitude of the acceleration a of the descending weight. a = m/s? Question Source: Freedman College Physics 3e | Publ

Suppose a 165 kg motorcycle has two wheels and is heading toward a hill at a speed of 30.0 m/s. Assume the wheels to be approximately an annular ring with an inner radius of  R1 = 0.280 m  and an outer radius of  R2 = 0.500 m.  The mass of each wheel is 12.3 kg. (a) How high can it coast up the hill in meters, if you neglect friction? (Give your answer to at least 1 decimal place.)  m (b) How much energy, in joules, is lost to friction if the motorcycle only gains an altitude of 35.0 m before coming to rest?  J

I need help with this problem please

A disk of radius = 2.02 mm is attached to a high-speed drill at a dentist’s office and is turning at 96,185 rad/sec. Determine the tangential speed of a point on the outer edge of this disk. Use g=9.8

A 250-g mass hangs from a string that is wrapped around a pulley, as shown in the figure. The pulley is suspended in such a way that it can rotate freely. When the mass is released, it accelerates toward the floor as the string unwinds. Model the pulley as a uniform solid cylinder of mass 1.00 kg and radius 5.00 cm. Assume that the thread has negligible mass and does not slip or stretch as it unwinds. Determine the magnitude a of the pulley's angular acceleration. rad/s? a = Determine the magnitude of the acceleration a of the descending weight. m/s? a = Calculate the magnitude of the tension T in the string. T = N Ouestien Source: Ereedman Cellege Dhycics 20 Dublich er: Mac mill

A potter is shaping a bowl on a a potter’s wheel.  The wheel rotaes at a constant angular speed.  The frictional force between her hands and the clay is 2.25 N.  How large is the torque she produces on the wheel if the diameter of the bowl is 14 cm.

A horizontal 790-N merry-go-round of radius 1.30 m is started from rest by a constant horizontal force of 45 N applied tangentially to the merry-go-round. Find the kinetic energy of the merry-go-round after 5.0 s. (Assume it is a solid cylinder. Also assume the force is applied at the outside edge.)