In the figure below, the biceps muscle exerts a force supporting a perpendicular forearm and a book. Suppose we replace the book with an elastic exercise rope that obeys Hooke's Law. Assume its force constant k = 453 N/m. Triceps muscle Biceps ´muscle PHYSICS m, = 4.3 kg CG Fe m, = 3.7 kg Wo CG 4.0 cm W. 16 cm- - 38 cm. (a) How much is the rope stretched (past equilibrium) to provide the same force w, as before the book was replaced? Assume the rope is held in the hand at the same location as the book. (Enter your answer in cm.) cm (b) What force (in N) is on the biceps muscle if the exercise rope is pulled straight up so that the forearm makes an angle of 18° with the horizontal? Assume the biceps musde is still perpendicular to the forearm. (Assume the same stretch in the rope as part (a). Enter the magnitude.) N

To strengthen his arm and chest muscles, a 79-kg athlete 2.0 m tall is doing a series of push-ups as shown in the figure below (Eigure 1). His center of mass is 1.15 m from the bottom of his feet, and the centers of his palms are 30.0 cm from the top of his head. Figure -2.0m 1 of 1 30.0 cm Find the force that the floor exerts on each of his feet, assuming that both feet exert the same force. Express your answer in newtons. F= Submit Part B F= [5] ΑΣΦ Submit Request Answer Find the force that the floor exerts on each of his hands, assuming both palms exert the same force. Express your answer in newtons. 1971 ΑΣΦ Request Answer ? N N

WNIFI Members AC and AB support the 300-lb crate. Determine the tensile force developed in member (AB). -3 ft 4 ft- 4 ft A Select one: a. F(AB) = 214 lb b. F(AB) = 114 lb c. F(AB) = 181.827 lb d. F(AB) = 282 lb A

A cook holds a 1.30 kg carton of milk at arm's length. What force FB must be exerted by the biceps muscle? (Ignore the weight of the forearm.) Nutrition Faete L 75.0° -25.0 cm: 8.00 cm