Concept explainers
|| At night while it is dark, a driver inadvertently parks his car on a drawbridge. Some time later, the bridge must be raised to allow a boat to pass through. The coefficients of friction between the bridge and the car’s tires are μs = 0.750 and μk = 0.550. Start each part of your solution to this problem with a free-body diagram of the car. (a) At what angle will the car just start to slide? (b) If the bridge attendant sees the car suddenly start to slide and immediately turns off the bridge's motor, what will be the car’s acceleration after it has begun to move?
Want to see the full answer?
Check out a sample textbook solutionChapter 5 Solutions
College Physics (10th Edition)
Additional Science Textbook Solutions
College Physics
The Cosmic Perspective Fundamentals (2nd Edition)
College Physics: A Strategic Approach (3rd Edition)
Life in the Universe (4th Edition)
Essential University Physics: Volume 1 (3rd Edition)
- || The 260kg crate shown in the figure rests on a horizontal surface for which the coefficient of kinetic friction is 0.25. If the crate is subjected to a 400 N towing force as shown determine the velocity of the crate in 5 s starting from rest PROBLEM 2 12 P = 400 N 30° The 80 kg block A shown in Figure is released from rest. If the masses of the pulleys and the cord are neglected determine the speed of the 12 kg block B in 3 s. SH Datumarrow_forward12. QCA block of mass 3.00 kg is pushed up against a wall by a force P that makes an angle of 0 50.0° with the horizontal as shown in Figure P5.12. The coeffi- cient of static fric tion between the block and the wall is 0.250. (a) Determine the possible values for the magnitude of P that allow the block to remain station- ary. (b) Describe what happens if |P has a larger value and what happens if it is smaller. (c) Repeat parts (a) and (b), assuming the force makes an angle of 0 13.0° with the horizontal. Figure P5.12arrow_forwardSubpart 1: Newton's Second Law along the y-axis (i) Write Newton's Second Law along the y-axis by adding all forces in the y-direction taking into account their signs (forces pointing upwards are positive and downward are negative) in terms of the normal force N, weight mg, F and 0. In both scenarios, there is no acceleration along the y-direction, therefore, a₁ = 0. ΣF,= (ii) Using (1) to solve for N. N= mg + Fsine✔✔✔✔ (2) -Fsin0+N-mg=may = 0 (1) Think: In (2) is N greater than the weight, less than the weight or equal to the weight? Subpart 2: Set up Newton's Second Law in the x-direction when the ice block is stationary. (i) Write Newton's Second Law along the x-axis by adding all forces in the x-direction taking into accountr their signs (forces pointing to the right are positive and pointing to the left are negative) when the block is not moving in terms of F, 0, and the force of static friction f. DON'T forget the subscript on fg. If the block is not moving, then ax = 0.…arrow_forward
- Three identical blocks connected by ideal (massless) strings are being pulled along a horizontal frictionless surface by a horizontal force F. The magnitude of the tension in the string between blocks B and C is T = 3.00 N . Assume that each block has mass m = 0.400 kg . What is the magnitude F of the force? What is the tension TAB in the string between block A and block B?arrow_forward7. A 400KN block is resting on a rough horizontal surface for which the coefficient of friction is 0.40. Determine the force P required to cause motion to impend if applied to the block 30° with the Horizontal. A. 225KN В. 23ОKN C. 235KN D. 240KN 8. A 400KN block is resting on a rough horizontal surface for which the coefficient of friction is 0.40. What minimum force is required to start motion? А. 138.5KN В. 148.5KN C. 158.5KN D. 168.5KNarrow_forwardhelparrow_forward
- Problem 2: An object weighing 5 N has an initial velocity of 180 km per hour. If the coefficient of kinetic friction is 0.2, determine the following: a) How far would the box travel until it comes to rest? b) How long would it take for the box to fully stop? Vi Vfarrow_forwardFigure P5.68 2. In Fig. P5.68 m, = 20.0 kg and a = 53.1°. The coefficient of kinetic friction between the block and the incline is Hg = 0.40. What must be the mass of the hanging block if it is to descend 12.0 m in the first 3.00 s after the system is released from rest? m2arrow_forward2. You are moving the box (m=1Okg) across a rough floor by pushing on it at an angle of 20° below the horizontal with force of magnitude F=100N. What is the coefficient of kinetic friction between the box and the floor if it is moving at constant velocity? Present free-body diagram. 10°arrow_forward
- А В 30° If the minions are originally at rest and Minion at B decided to hang on the pulley. Minion at A has a mass of 90 kg while minion at B has a mass of 160 kg. Determine the following if the masses of the pulleys are neglected and the friction between the minion at A and the incline are s = 0.25 and k = 0.20. a. FBD of each minion. b. The acceleration of each minion. c. The tension in the cable.arrow_forwardᎾ X A loaded penguin sled with a mass m = 10.0 kg rests on a plane inclined at angle 0 = 20.0° to the = 0.300, and the horizontal. Between the sled and the plane, the coefficient of static friction is μs coefficient of kinetic friction is μk = 0.100. We want to find the magnitude of force F that is necessary to make the sled move up the plane. 1) Draw a free body diagram of forces acting on the slate (1 point) 2) Write the projection of the gravity force vector on the x and y axis, where x is parallel to the surface and y perpendicular to it as shown on the figure. (1 point) 3) Apply the Newton's second law separately to the x and y axis to obtain two equations. (2 points) 4) From the two equations obtained previously, find the value of the pulling force F necessary to start to move the sled. (2 points) 5) After the sled started to move it reaches a constant velocity v. Compute the force F necessary to maintain the motion of the sled at a non-zero velocity. (1 point)arrow_forward4arrow_forward
- College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningUniversity Physics (14th Edition)PhysicsISBN:9780133969290Author:Hugh D. Young, Roger A. FreedmanPublisher:PEARSONIntroduction To Quantum MechanicsPhysicsISBN:9781107189638Author:Griffiths, David J., Schroeter, Darrell F.Publisher:Cambridge University Press
- Physics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningLecture- Tutorials for Introductory AstronomyPhysicsISBN:9780321820464Author:Edward E. Prather, Tim P. Slater, Jeff P. Adams, Gina BrissendenPublisher:Addison-WesleyCollege Physics: A Strategic Approach (4th Editio...PhysicsISBN:9780134609034Author:Randall D. Knight (Professor Emeritus), Brian Jones, Stuart FieldPublisher:PEARSON