In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force F A of magnitude 214 N, and Charles pulls with force F c of magnitude 175 N. Note that the direction of F c is not given. What is the magnitude of Betty's force F B if Charles pulls in (a) the direction drawn in the picture or (b) the other possible direction for equilibrium? Alex Charles 147° Betty

A block is resting on a wooden plank. There is a hinge on one end of the plank which allows the other end to be lifted to create an angle, θ, with respect to the horizontal as shown in the figure. The coefficient of static friction between the block and the plank is μs. If a student measures that the block begins to move at an angle of θ = 20.5°, what is the numerical value of the coefficient of static friction, μs?

Problems 1. Three forces act on particle A located at the origin of an x-y coordinate system. Force B acts at 140° from the positive x-axis, and force C acts at 15° from the positive x-axis. The weight acts down with a magnitude of W = 100 kN. Use the equations of equilibrium to determine the magnitudes of B and C such that particle A is in equilibrium. For problems 2-5, consider the following scenario. Equilibrium of a particle: EF=0 XFx=0 and ΣFy=0. Dimensions are: h = 2.5 ft, d₁ = 4.75 ft, and d₂ = 3 ft. Give numeric answers to three significant figures. The load W = 50 lb. d₁ dz A h α W B

In a tug-of-war game on one campus, 15 students pull on a rope at both ends in an effort to displace the central knot t one side or the other. Two students pull with force 198 N each to the right, four students pull with force 94 N each to the left, five students pull with force 60 N each to the left, three students pull with force 160 N each to the right, and one student pulls with force 260 N to the left. Assuming the positive direction to the right, express the net pull on the knot (in N) in terms of the unit vector i. N Fnet = How big is the net pull on the knot (in N)? (Enter the magnitude.) N What direction is the net pull on the knot? O to the right O to the left O The magnitude is zero. Additional Materials Reading