Battle of the Revolving DoorEXAMPLE 8.1GOAL Apply the basic definition of torque.PROBLEM Two disgruntled businesspeople are trying to use a revolvingdoor, as in the figure. The woman on the left exerts a force of 625 Nperpendicular to the door and 1.20 m from the hub's center, while the manon the right exerts a force of 8.50 x 10² N perpendicular to the door and0.800 m from the hub's center. Find the net torque on the revolving door.SOLUTIONCalculate the torque exerted by thewoman. A negative sign must besupplied because F₁, if unopposed,1'would cause a clockwise rotation.STRATEGY Calculate the individual torques on the door using the definitionof torque, and then sum to find the net torque on the door. The womanexerts a negative torque, the man a positive torque. Their positions of application also differ.Calculate the torque exerted by theman. The torque is positive becauseF2, if unopposed, would cause acounterclockwise rotation.Sum the torques to find the net torqueon the door.+2:||TnetT₁ = -₁ F₁ = -(1.20 m)(625 N) = -7.50 × 10² N·mF₁=7= -7.0 × 10¹ N.m− r₂F2 = (.80 m)(850 N) = 6.80 × 10² N. mT₁+T₂:1410² PRACTICE ITUse the worked example above to help you solve this problem. Two disgruntled businessmen are trying touse a revolving door, as shown in the figure. The door has a diameter of 2.60 m. The businessman on theleft exerts a force of 647 N perpendicular to the door and 1.1 m from the hub's center, while the one onthe right exerts a force of 806 N perpendicular to the door and 0.528 m from the hub's center. Find thenet torque on the revolving door. (Indicate the direction with the sign of your answer.)N•mEXERCISEGETTING STARTED | I'M STUCK!A businessman enters the same revolving door on the right, pushing with 528 N of force directedperpendicular to the door and 0.621 m from the hub, while a boy exerts 388 N perpendicular to the door,1.35 m to the left of the hub. (Indicate the direction with the sign of your answer.)(a) Find the torques exerted by each person.N•mTboyman==N•m(b) Find the net torque on the door.N•mTnetHINTS:

Answered: Image /qna-images/answer/1f0a0e9d-4f06-449c-9a0e-41889330072d.jpg

N m EXERCISE HINTS: GETTING STARTED II'M STUCK! A businessman enters the same revolving door on the right, pushing with 528 N of force directed perpendicular to the door and 0.621 m from the hub, while a boy exerts 388 N perpendicular to the door, 1.35 m to the left of the hub. (Indicate the direction with the sign of your answer.) (a) Find the torques exerted by each person. boy = N m man = N m (b) Find the net torque on the door. net = N.m

N m EXERCISE HINTS: GETTING STARTED II'M STUCK! A businessman enters the same revolving door on the right, pushing with 528 N of force directed perpendicular to the door and 0.621 m from the hub, while a boy exerts 388 N perpendicular to the door, 1.35 m to the left of the hub. (Indicate the direction with the sign of your answer.) (a) Find the torques exerted by each person. boy = N m man = N m (b) Find the net torque on the door. net = N.m

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

F2 30.0 O K 2.00 m 3.00m->l Find the net (or total) torque about point O for the two forces as in the figure above. let F₁ = 7.80N and F₂=15. ON Express your answer in newton-meters. VF1
The body in the figure below is pivoted at point (), and two forces act on it as shown. → If ri = 1.3 m, r2 = 2.15 m, F₁ 4.2 N, F₂ = 4.9 N, 01 = 75° and 0260°, what is the net torque (in N·m) about the pivot? 14.3 X
g disk with a radius a 0.500 m is subjected to three tangential forces of constant as shown below. The moment of inertia is Idisk =mr?. F2 and F3 are applied on the of the disk while F, is applied at 0.300 m from the center. Assume the rotation is enter of the disk.
EXERCISE HINTS: GETTING STARTED I'M STUCK! A man ties one end of a strong rope 7.68 m long to the bumper of his truck, 0.534 m from the ground, and the other end to a vertical tree trunk at a height of 3.86 m. He uses the truck to create a tension of 7.73 x 10 N in the rope. Compute the magnitude of the torque on the tree due to the tension in the rope, with the base of the tree acting as the reference point. N. m
A kitchen door is attached to a vertical support by a set of hinges. Assume the door is uniform and has height 2.40 m, width 0.865 m, and mass 21.0 kg. A. Determine its moment of inertia (in kg · m2) for rotation on its hinges. B. Are any pieces of data unnecessary? (Select all that apply.) The height of the door is unnecessary. The width of the door is unnecessary. The mass of the door is unnecessary. No; all of the data are necessary.
The fishing pole in the figure below makes an angle of 20.0° with the horizontal. What is the magnitude of the torque exerted by the fish about an axis perpendicular to the page and passing through the angler's hand if the fish pulls on the fishing line with a force F = 125 N at an angle 37.0° below the horizontal? The force is applied at à point L = 1.92 m from the angler's hands. N.m -I 20.0° 37.0 1 20.0° F
a. What is the maximum torque applied by the cable? (Give your answer in N m.) b. What is the torque due to the weight of the bridge? (Give your answer in N m.) c. How far can Lancelot ride out along the bridge before the cable breaks? (Give your answer in m.) Note: At his maximum distance, the torque from the cable will equal the torque from both the weight of the bridge and the weight of Lancelot.
Inigo and Fezzik push with perpendicular forces on a heavy door with width R. Inigo pushes with force F at 3R/4 from the hinge, while Fezzik pushes with force 2F at R/3 from the hinge. Which of the following descriptions is correct? (diagram shows the top-down view) hinge O B ОА A. Inigo (pushing with F) exerts a greater a torque on the door. B. Fezzik (pushing with 2F) exerts a greater a torque on the door. C. The torques they exert are equal in magnitude. D. There is zero net torque on the door. OD 3R/4 O C R/3 2F
In the rotational motion experiment, a student wanted to measure the moment of inertia I of a disc, If he found out that the torque acting on the disc to be 2.7 N.m and the angular acceleration to be 21.01 rad/s?, find the moment of inertia ( in units of kg. m²) of the disc. Select one: O A. 0.129 B. 0.231 O c. 0.090 O D. 0.064 O E. 0.193
A solid disk with an axis of rotation through the center (perpendicular to the diagram). Two holes are cut out near the center and the material is placed near the rim. Which has the larger I? Please explain your conclusion.
Sierra holds a box in her hand using her elbow flexor muscles (see picture). Her forearm is at a 35° angle relative to the horizontal. b.) What is the magnitude and direction (+ or -) of the torque caused by the weight of the box (box weight = 43.00 N)? Upload