15) A uniform ladder having a weight of 150. N rests against a wall, making an angle of 60.00 up from the ground. Both the ground and the wall are frictionless surfaces, requiring a rope tied near the bottom of the ladder to prevent the base of the ladder from slipping left and the top of the ladder from sliding down. If the rope can reach a maximum tension of 450 N prior to breaking, how far up the ladder can a 700.-N person climb? The ladder is 3.00 m long and the rope is attached 0.500 m from its base. An incomplete free-body diagram is provided: 3.0 m x = ? ladder person 60° rope

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 ?

2. A 3.0-m-long ladder leans against a wall at an angle of 60° with respect to the floor. What is the minimum value of us, the coefficient of static friction with the ground, that will prevent the ladder from slipping? Assume that friction between the ladder and the wall is negligible. Center of gravity 19 TULO L 60⁰ Weight acts at the center of gravity. Known L-30 m Find Me Contro <= 0 about this point. Static friction prevents slipping.

4. A uniform beam of mass m, and length L is supported as shown below. There is a pin in theb bottom end of the beam and a mass of mass m, hanging from the top end of the beam. Find the magnitude of the tension in the wire attaching the beam to the ground and force from the pin on the beam.

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2. A 14.0 m uniform ladder weighing 520 N rests against a frictionless wall. The ladder makes a 55.0°-angle with the horizontal. a) Find the horizontal and vertical forces (in N) with its direction, for the ground exerts on the base of the ladder when an 820-N firefighter has climbed 3.90 m along the ladder from the bottom.   b) If the ladder is just on the verge of slipping when the firefighter is 9.20 m from the bottom, what is the coefficient of static friction between ladder and ground?   c) What If? If oil is spilled on the ground, causing the coefficient of static friction to drop to half the value found in part (b), what is the maximum distance (in m) the firefighter can climb along the ladder from the bottom before the ladder slips?

b) Determine the horizontal and vertical components of the force acting on the hing 3. A uniform 4.0 m long beam with a mass of 15 kg rests on a pivot at one end and is kept horizontal by a cable at the other end. The beam is supporting a 25 kg mass as shown. What is the tension in the cable? pluct 15 kg beam 2.5m - Fird ferce or support) сп вест of 25 kg -1.5 m 55⁰ 55° weight of beam = middle weight of dhject = pa te middle on

3. A uniform ladder of mass (m = 13.0 kg) and length (L) leans against a frictionless wall, see figure. If the angle 8 68.0°, find the static friction force between the ladder and the floor when a 85.0-kg person stands one- = third of the way up the ladder? N A L Ꮎ

A uniform 22 kg beam, 3.0 m long, is attached to a wall on the left by a hinge, and is supported by a cable on its right end. A 13 kg monkey hangs from the beam, 1.0 m from the left end. a) Determine the tension in the cable. b) Determine the magnitude of the force due to the hinge on the beam.

6) The system shown in in equilibrium. A mass of 225 kg hangs from theend of the strut, which is connected by a hinge to the ground and makes anangle of 45 degrees with the ground. The strut has a mass of 45.0 kg. Asupport cable is attached from a wall to the center of the strut and it makesan angle of 70 degrees with the vertical wall. a) Find the tension in the cable holding up the strut, which make anangle of 70 degrees with the wall. b)  Find the horizontal and vertical forces exerted on the strut by the hinge.