A 75 kg uniform plank is supported by the floor at one end and by a vertical rope at the other end as shown in the figure. A 32 kg mass person stands on the plank a distance three-fourth of the lenght plank from the end on the floor. a- Draw a force diagram for the plank. Write net force and net torqueequations for the plank. b-What is the tension in the rope? c-What is the magnitude of the force that the floor exerts on the plank?

(a) Give an example in which the net force acting on an object is zero and yet the net torque is nonzero, (h) (five an example in which the net torque acting on an object is zero and yet the net force is nonzero.

(a) Is it possible to calculate the torque acting on a rigid object without specifying an origin? (b) Is the torque independent of the location of the origin?

The forearm shown below is positioned at an angle with respect to the upper arm , and a 5.0- kg mass is held in the hand. The total mass of the forearm and hand is 3.0 kg, and their center of mass is 15.0 cm from the elbow. (a) What is the magnitude of the force that the biceps muscle exerts on the forearm for =60 ? (b) What is the magnitude of the force on the elbow joint for the same angle? (c) How do these forces depend on the angle ?

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

A massless, horizontal beam of length L and a massless rope support a sign of mass m (Fig. P14.78). a. What is the tension in the rope? b. In terms of m, g, d, L, and , what are the components of the force exerted by the beam on the wall? FIGURE P14.78

A 40 kg, 5.0-m-long beam is supported by, but not attached to, the two posts A and B in the figure. A 20 kg boy starts walking along the beam and stops 1.2 m from the right end of the beam. The beam does not tip. A B 3.0 m a) Draw a fully labelled force diagram for the beam. b) Calculate the magnitude of the force exerted by the post B on the beam.

If an object is in equilibriuim, the net torque about any arbitrary axis must be zero. A. True B. False

A 10.2 kg box (Weight = Fg= 100 N) is at one end of a massless board (1.5 m from the fulcrum). a. How much mass (m) do you have to have at the other end (1.5 m from the fulcrum) to get it to balance? b. How much weight (Fg )? c. How hard do you have to push to begin to lift the box?

Two forces are acting on an object. Which of the following statements are correct?   a. The object is in equilibrium if the forces are equal in magnitude and opposite in direction. b. The object is in equilibrium if the net torque on the object is zero. c. The object is in equilibrium if the forces act at the same point on the object. d. The object is in equilibrium if the net force and the net torque on the object are both zero. e. The object cannot be in equilibrium because more than one force acts on it.