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You hang a light in front of your house using an elaborate system to keep the 12- kg light in static equilibrium (see Figure P8.8). What are the magnitudes of the forces that the ropes must exert on the knot connecting the three ropes if
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- 17 kg uniform store sign is held from a uniform horizontal beam as shown. There is a cable attached to the right edge of the beam and is secured to the wall, 250 cm above where the beam meets the wall. The sign is symmetrically suspended by two cords, the left cord being 80 cm from the wall, and the cord on the right being at the right edge of the beam, 200 cm from the wall. a. What is the tension in the left and right cords that hold the sign? b. What is the tension in the cable? c. What is the horizontal component of the force that the wall exerts on the beam?arrow_forwardAn outdoor chair is suspended from a tree by a single cable of length 1.5 m. The mass of the chair and the person sitting in it is a total of 85 kg. If someone pulls the chair through a horizontal distance of 80 cm and holds it there: a. What is the increase in the force exerted by the cable? b. How much sideways force must be exerted to hold the chair at that location?arrow_forwardtivityBranding&COURSEID=5110&SECTIONID=293095 1. A meter rule is anchored at the point O and is free to rotate about an axis passing through O and perpendicular to the plane of the meter rule. Forces F₁, F2, F3, F4 and F5 of equal magnitudes act on the ruler at different locations. The magnitude of each force is 24 N and 0 =30°. The distances along the ruler are given in cm. Search F₁ 30 0 12.47 F₂ 60 0 99- F4 A 100 Fs (a) Determine whether each force can or cannot rotate the ruler and select the correct rationale for your answer. F₁ No, because it is on the F₂ Yes F3 Yes F₁ Yes Fs No, because the force iv (b) Between F3 or F4 which force produces a larger torque? F3-because it is perpe (c) Calculate the torques produced by F3 and F4, including the sign of the torque indicating the sense of rotation, positive for counter-clockwise rotation and negative clockwise rotation. h Help: When using the formula for torque, the angle is between the tails of which two vectors? Draw a diagram…arrow_forward
- The chewing muscle, the masseter, is one of the stron- gest in the human body. It is attached to the mandible (lower jawbone) as shown in Figure P8.33a. The jawbone is pivoted about a socket just in front of the auditory canal. The forces acting on the jawbone are equivalent to those acting on the curved bar in Figure P8.33b. F. is the force exerted by the food being chewed against the jawbone, T is the force of ten- sion in the masseter, and R is the force exerted by the socket on the mandible. Find T and R for a person who bites down on a piece of steak with a force of 50.0 N. 3.50 cm – 7.50 cm Masseter Mandible Б a Figure P8.33arrow_forwardAnswer the following questions. 1. A box of weight 100 N hangs from the rope. The rope weighs 50 N and is uniform. What is the tension in the rope? a. 100 N throughout the rope b. 150 N throughout the rope It varies from 100 N at the bottom of the rope to 150 N at the с. top. A block of weight 25 kg is resting on an inclined surface with dimensions of 4 meter wide and 3 m high (See figure at the fight). Find the following: 2. Which of the following about the figure NOT true? Given wotating the axes 37 degrees clockwise. a. Fx=Ff-245sin37 b. Fx=Ff-25sin37 5m c. Fx=Ff-245cos 37 d. Fx=Ff-245sin37 3 m 3. Which of the following about the figure NOT true? Given 37 otating the axes 37 degrees clockwise. a. Fy=N-245cos37 b. Fy=N-245sin37 c. Fy=N-25cos37 d. Fy=N-25sin37 4. Find the Normal force Nacting on the object. a. 19.96 N b. - 19.86 N c. 195.66 N d. 147.44 N 4 m 5. Find the friction force Ff a. 19.96 N b. - 19.86 N c. 195.66 N d. 147.44 N 6. Find the coefficient of static friction µ. a.…arrow_forwardThe system shown in the figure is in equilibrium. If the block has a mass of 7 kg and the angle θ = 32. What is the tension in the string connecting the block to the wall? Express your answer in Newtons.arrow_forward
- 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 thnarrow_forwardDetermine the force-couple system at O which is equivalent to the two forces applied to the shaft AOB. Is R perpendicular to Mo? Assume F1 = 600 N, F2 = 610 N, a = 75 mm, b = 170 mm, 0 = 20°, and o = 54°. A a b. B F, Answer: R = (i i+ i j+ i k) N Mo = ( i i+ i j+ i k) N-marrow_forwardA force F making an angle of 30° with the horizontal maintains a box with mass m = 8 kg in static equilibrium on a frictionless vertical wall. What is the magnitude of the applied force? Use g = 10 m/s?. %3D O 80 N 120 N O 140 N O 160 N O 100 Narrow_forward
- 100 g A 54 g uniform meter stick is to be suspended by a single string A 100-g block hangs from the left-hand edge of the meter stick Where should the string be attached so that the meter stick is in equilibrium? Briefly explain how you solved the problem. BI T.arrow_forwardThe experiment you did in lab is repeated, using a uniform metal bar that is 80.0 cm long instead of the meterstick. Since the bar is uniform, its center of gravity is at its center. The new experiment uses different hooks for hanging the masses from the bar, with mhook 5.0 g. As in the experiment you did in lab, X1 = 5.00 cm, m1 300.0 g, and Xp = 25.0 cm. In the 1 new experiment, you make the same measurements as in your lab and plot x versus The line that is the best fit to your data has slope 3800 cm · g. What is the mass of m2 + mhook the bar?arrow_forwardTwo friends are carrying a 500 N wooden slab along a 45 degrees stairway. The slab is 1.0 m long and 0.40 m high. They each apply vertical upward force (black arrows) on the bottom edges of the box in such a way that the box remains parallel to the stairs as shown in the figure. What are the magnitudes of theforces exerted by the lower and higher friend, respectively?arrow_forward
- College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning