3. A very light rod of length 3L is pivoted at one end so it can rotate without friction on a flat table top. A mass M is attached to the rod a distance L from the pivot and a second mass 2M is attached to the opposite end from the pivoted end as shown in the figure. What is the ratio of the tension T1 to T2 ? That is, calculate T1/T2. шк 2M 3L M w Pivot Point

3. A very light rod of length 3L is pivoted at one end so it can rotate without friction on a flat table top. A mass M is attached to the rod a distance L from the pivot and a second mass 2M is attached to the opposite end from the pivoted end as shown in the figure. What is the ratio of the tension T1 to T2 ? That is, calculate T1/T2. шк 2M 3L M w Pivot Point

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter8: Rotational Motion

Section: Chapter Questions

Problem 5STP

See similar textbooks

Similar questions

Find the net torque on the wheel in Figure P10.23 about the axle through O, taking a = 10.0 cm and b = 25.0 cm. Figure P10.23
A rope of negligible mass is wrapped around a 225 kg solid cylinder of radius 0.400 m. The cylinder is suspended several meters off the ground with its axis oriented horizontally, and turns on that axis without friction, (a) If a 75.0-kg man takes hold of the free end of the rope and falls under the force of gravity, what is his acceleration? (b) What is the angular acceleration of the cylinder? (c) if the mass of the rope were not neglected, what would happen to the angular acceleration of the cylinder as the man falls?
The combination of an applied force and a friction force produces a constant total torque of 36.0 N m on a wheel rotating about a fixed axis. The applied force acts for 6.00 s. During this time, the angular speed of the wheel increases from 0 to 10.0 rad/s. The applied force is then removed, and the wheel comes to rest in 60.0 s. Find (a) the moment of inertia of the wheel, (b) the magnitude of the torque due to friction, and (c) the total number of revolutions of the wheel during the entire interval of 66.0 s.
A bar on a hinge starts from rest and rotates with an angular acceleration = 10 + 6t, where is in rad/s2 and t is in seconds. Determine the angle in radians through which the bar turns in the first 4.00 s.
The fishing pole in Figure P10.22 makes an angle of 20.0 with the horizontal. What is the torque exerted by the fish about an axis perpendicular to the page and passing through the anglers hand if the fish pulls on the fishing line with a force F=100N at an angle 37.0 below the horizontal? The force is applied at a point 2.00 m from the anglers hands. Figure P10.22
An electric sander consisting of a rotating disk of mass 0.7 kg and radius 10 cm rotates at 15 rev/sec. When applied to a rough wooden wall the rotation rate decreases by 20 . (a) What is the final rotational kinetic energy of the rotating disk? (a) How much has its rotational kinetic energy decreased?
A baseball catcher extends his arm straight up to catch a fast ball with a speed of 40 m/s. The baseball is 0.145 kg and the catcher’s arm length is 0.5 m and mass 4.0 kg. (a) What is the angular velocity of the arm immediately after catching the ball as measured from the arm socket? (b) What is the torque applied if the catcher stops the rotation of his arm 0.3 s after catching the ball?
A large grinding wheel in the shape of a solid cylinder of radius 0.330 m is free to rotate on a friction less, vertical axle. A constant tangential force of 250. N applied to its edge causes the wheel to have an angular acceleration of 0.940 rad/s2. (a) What is the moment of inertia of the wheel? (b) What is the mass of the wheel? (c) If the wheel starts from rest, what is its angular velocity after 5.00 s have elapsed, assuming the force is acting during that time?
A uniform cylindrical grinding wheel of mass 50.0 kg and diameter 1.0 m is turned on by an electric motor. The friction in the bearings is negligible. (a) What torque must be applied to the wheel to bring it from rest to 120 rev/min in 20 revolutions? (b) A tool whose coefficent of kinetic friction with the wheel with a force of 40.0 N. What torque must be supplied by the motor to keep the wheel rotating at a constant angular velocity?
Three identical thin rods, each of length L and mass m, are welded perpendicular to one another as shown in Figure P10.43. The assembly is rotated about an axis that passes through the end of one rod and is parallel to another. Determine the moment of inertia of this structure about this axis.
A spool of thread consists of a cylinder of radius R1 with end caps of radius R2 as depicted in the end view shown in Figure P10.45. The mass of the spool, including the thread, is m, and its moment of inertia about an axis through its center is I. The spool is placed on a rough, horizontal surface so that it rolls without slipping when a force T acting to the right is applied to the free end of the thread. (a) Show that the magnitude of the friction force exerted by the surface on the spool is given by f=(I+mR1R2I+mR22)T (b) Determine the direction of the force of friction. Figure P10.45
The fishing pole in Figure P10.28 makes an angle of 20.0 with the horizontal. What is the torque exerted by the fish about an axis perpendicular to the page and passing through the anglers hand if the fish pulls on the fishing line with a force F = 100 N at an angle 37.0 below the horizontal? The force is applied at a point 2.00 in from the anglers hands.