A patient rehabilitating a knee injury performs knee extension exercises while wearing a 35 N weight boot. Calculate the amount of torque about the knee joint generated by the weight boot for each of the four positions shown, given a distance of 0.3 m from the knee joint center to the center of mass of the weight boot. Ignore the weight of the leg. Be sure to provide the correct direction of the torque. P₂0

The counterclockwise rotation of the blade of a grinder is dying down. Which of the following is true about the directional relations of the angular velocity, acceleration, and net torque? a and w is directed in -z-axis, while 7 is at +z-axis. O T and a is directed in +z-axis, while w is at -z-axis. T and a is directed in -z-axis, while w is at +z-axis. O T, a and w have the same direction which is into the page. O T, a and w have the same direction which is out of the page.

Find the net torque on the wheel as shown about the axle through O, taking a = 10.0 cm and b = 25.0 cm.

In our class model, wind is flowing along the X axis and torque is generated in the Y axis, with torque measurements in the other axes being near 0. What would happen in reality if the torque in the X axis were large, even larger than in the Y axis? (select only one) The turbine would spin really fast and produce more energy O The turbine would not spin at all The wind could tip over the turbine O The turbine would spin backwards 1or hoth 2 a nd 2

Compute the combined moment of the two 50-lb forces about (a) point O and (b) point A. The moment is positive if counterclockwise, negative if clockwise. Assume a = 5.5 in., b = 2.5 in., F = 50 lb. Answers: (a) Mo= (b) MA= M. lb-in. lb-in. X

A thin spherical shell has a radius of 0.90 m. An applied torque of 920 N m imparts to the shell an angular acceleration equal to 4.70 rad/s2 about an axis through the center of the shell. What is the rotational inertia of the shell about the axis of rotation? Calculate the mass of the shell.

Modern wind turbines generate electricity from wind power. The large, massive blades have a large moment of inertia and carry a great amount of angular momentum when rotating. A wind turbine has a total of 3 blades. Each blade has a mass of m = 5500 kg distributed uniformly along its length and extends a distance r = 44 m from the center of rotation. The turbine rotates with a frequency of f = 12 rpm. a)Calculate the total moment of inertia of the wind turbine about its axis, in units of kilogram meters squared.  b)Enter an expression for the angular momentum of the wind turbine, in terms of the defined quantities.  c)Calculate the angular momentum of the wind turbine, in units of kilogram meters squared per second.

12.0 N 30.0% b 10.0 N 9.00 N The figure shows one cylinder inside another. The inner cylinder has a radius of a = 0.5 m and a mass of 2 kg. The outer cylinder has a radius b = 1.5 m and a mass of 12 kg. On the system act 4 forces. Those shown in figure 2 and a friction force. If the magnitude of the frictional torque is 1.75 mN. Determine: a. The net torque vector on the system. (Magnitude and direction) b. The total moment of inertia of the system

Newton's second law for linear motion is mà The equivalent form for rotational motion is - là, where is torque, I stands for the moment of inertia, and is the angular acceleration. The effectiveness of the applied torque is determined by: O The amount of Force applied The distance of the applied force from the axis of rotation. O The angle between the applied force vector Fand the vector distance from the axis of rotation to the applied point of the force O All of the above

A 7.83 kg particle with velocity = (1.81 m/s )i - (9.64 m/s ) is at x = 8.83 m.y = 1.23 m. It is pulled by a 9.44 N force in the negative x direction. About the origin, what are (a) the particle's angular momentum, (b) the torque acting on the particle, and (c) the rate at which the angular momentum is changing? (a) Number (b) Number (c) Number : Units Units Units