Box A, weighting 60 N, is placed on a table tilted at angle of 15˚. Another box, B, weighing 40N, is placed on top of A. Both boxes are at rest. A) Draw the free-body diagram for box B. What is the frictional force exerted on A by B? B) Draw the free-body diagram for box A. What is the frictional force exerted on A by the table?

When a person stands on tiptoe (a strenuous position), the position of the foot is as shown in Figure a. The total gravitational force on the body, F, is supported by the force n exerted by the floor on the toes of one foot. A mechanical model of the situation is shown in Figure b, where T is the force exerted by the Achilles tendon on the foot and R is the force exerted by the tibia on the foot. Find the values of T, R, and e when F, = n = 675 N. (For e, enter the smaller of the two possible values between 0° and 90°.) Achilles tendon Tibia 15.0° 18.0 cm 25.0 cm T = N R = N Need Help? Read It

Most of the motion generated by joints in the human body are examples of levers. An example of a third class lever is the forearm; the force which generates the motion is located in-between the pivot point and the resistance force. The elbow acts as the pivot point, the biceps muscle pulls up on the forearm to move the mass which is held in the hand. Imagine someone is holding an object in her hand with her forearm horizontal and her upper arm vertical so her elbow creates a 90° angle. If her biceps attach to her forearm 0.0511 m from the elbow and make an angle of 26.0° with the vertical while a 2.76 kg mass is held in her hand 29.89 cm from the elbow, what force F is exerted by the biceps muscle? Ignore the mass of the forearm. F =

F. y M. mg AF FY f.Y Fixle Axis The ladder in the picture has a mass of 39 kilograms and a length 3.4 meters. What is the normal force pushing the ladder up from the floor? This force is labeled Ff v in the picture. FN Assume that the ladder's weight is evenly distributed, so it can be treated as a single force through the middle. If the ladder is at a 70° angle from the ground, what is the torque exerted by the weight (using the floor as the pivot point)? N.m The torque from the ladder must be balanced by the torque caused by the normal force on the wall, labeled Fw in the picture. Calculate this force. Fw = The normal force from the wall must be balanced by the friction force from the floor, labeled Ff y in the picture Determine thn

A system comprised blocks, a light frictionless pulley, and connecting ropes is shown in the figure. The B block has a mass of 9.3 kg and is on a perfectly smooth horizontal table. The surfaces of the A block, which has a mass of 8.2 kg, are rough, with μk=μk= 0.25 between the block and the table. If the C block with mass 9.9 kg accelerates downward when it is released, find its acceleration.

The wheels, axle, and handles of a wheelbarrow weigh W = 57 N. The load chamber and its contents weigh W₁ = 563 N. The drawing shows these two forces in two different wheelbarrow designs. To support the wheelbarrow in equilibrium, the man's hands apply a force to the handles that is directed vertically upward. Consider a rotational axis at the point where the tire contacts the ground, directed perpendicular to the plane of the paper. Find the magnitude of the man's force for both designs. F F (a) F = (b) F = i i W 0.400 m ¹0.700 m 0.200 m (a) > > 0.600 m' 0.700 (b)

When a person stands on tiptoe (a strenuous position), the position of the foot is as shown in Figure a. The total gravitational force on the body,  Fg,  is supported by the force  n  exerted by the floor on the toes of one foot. A mechanical model of the situation is shown in Figure b, where  T  is the force exerted by the Achilles tendon on the foot and  R  is the force exerted by the tibia on the foot. Find the values of T, R, and ? when  Fg = n = 720 N.  (For ?, enter the smaller of the two possible values between 0° and 90°.)   T should be in the 1700-1800 range, please be careful and not give a wrong answer, thanks :)

To run Slap-chop and use Sham-wow you need to be in shape. For a work out, the man in the figure uses a device consisting of four springs arranged as shown. Each spring has a spring constant of 75.5 N/m. The hands holding the unstretched device are 36.34 cm apart. If the person can extend the springs to 61.87 cm apart, what is the maximum lateral force exerted by each hand?

Consider the pulley system depicted in the figure. The block is prevented from moving by the applied force F.  Assume the pulleys are massless and frictionless.   An illustration shows a rectangular block of mass M suspended from a horizontal surface by a complex pulley system comprised of one large pulley, one small pulley, two short ropes, and one long rope. The pulleys are drawn such that the small pulley is some vertical distance below the large pulley and their axles are perpendicular to the page. The left side of the small pulley aligns vertically with the center of the large pulley. One of the short ropes suspends the block of mass M from the bottom of the small pulley's harness and has tension T5. The remaining short rope and the long rope are, respectively, anchored to the top and bottom of the large pulley's harness. This short rope has tension T4 and suspends the large pulley from the horizontal surface. The long rope extends from the large pulley and cradles the small…

As shown on the right, a uniform rod with a weight W= 100 N and a length L = 2.0 m is hinged at the bottom end and is vertical. A light cable, tied to the rod at a height of h = 1.0 m, makes an angle 0 = 40° from the horizontal. A horizontal force F= 50 N is exerted at a height H = 1.5 m on the rod. (a) Draw a free-body diagram for the rod.(b) What is the tension in the cable?(c) What are horizontal and vertical components ofthe force exerted on the rod at the hinge?