2. An engine with weight w hangs from a chain that is linked at a point O to two other chains, one is connected to the ceiling and the other one to the wall, Find the tension in each of the three chains, assuming that w is given and the weights of the chains are negligible. The angle of separation between the wall and the ceiling is 45'. we e weh y it n) Car on ae Freoy am

Bd 11. Need a b and c

Choose the coefficient of friction wisely. Relevant information is given in the textbook. a. What is the maximum frictional force in the knee joint of a person who supports 70.0 kg of her mass on that knee? Fmax 686.7 XN b. During strenuous exercise it is possible to exert forces to the joints that are easily ten times greater than the weight being supported. What is the maximum force of friction under such conditions? (The frictional forces in joints are relatively small in all circumstances except when the joints deteriorate, such as from injury or arthritis. Increased frictional forces can cause further damage and pain.) Fmax = N

A-10 N falling object encounters +4 N of air resistance directed upward. The net force acting on the object is therefore object will O a.0N/Fall at one speed. b.4 N directed upwards / The object will slow down. Oc.-6 N directed down / The object will accelerate. Od. 10 N/ The object will be at rest. The MacE esc ! @ # $ 1 3 4 6. Q W R A S F ck C V rel aption Command

(a) Calculate the tension (in N) in a vertical strand of spiderweb if a spider of mass 7.00 x 105 kg hangs motionless on it. (Enter a number.) N (b) Calculate the tension (in N) in a horizontal strand of spiderweb if the same spider sits motionless in the middle of it much like the tightrope walker in the figure. 5.0° 5,0° T. TR T I Ta w The strand sags at an angle of 12.0° below the horizontal. (Enter a number.) N Compare this with the tension in the vertical strand (find their ratio). (Enter a number.) (tension in horizontal strand)/(tension in vertical strand) =