Concept explainers
If your car is stuck in the mud and you don't have a winch to pull it out, you can use a piece of rope and a tree to do the trick. First, you tie one end of the rope to your car and the other to a tree, then pull as hard as you can on the middle of the rope, as shown in Figure P4.68 a. This technique applies a force to the car much larger than the force that you can apply directly. To see why the car experiences such a large force, look at the forces acting on the center point of the rope, as shown in Figure P4.68 b. The sum of the forces is zero, thus the tension is much greater than the force you apply. It is this tension force that acts on the car and, with luck, pulls it free.
Figure P4.68
71. Suppose your efforts work, and the car begins to move forward out of the mud. As it does so, the force of the car on the rope is
A. Zero.
B. Less than the force of the rope on the car.
C. Equal to the force of the rope on the car.
D. Greater than the force of the rope on the car.
Want to see the full answer?
Check out a sample textbook solutionChapter 4 Solutions
College Physics: A Strategic Approach (3rd Edition)
Additional Science Textbook Solutions
Cosmic Perspective Fundamentals
Brock Biology of Microorganisms (15th Edition)
Human Physiology: An Integrated Approach (8th Edition)
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Campbell Biology (11th Edition)
Organic Chemistry (8th Edition)
- An object of mass m = 1.00 kg is observed to have an acceleration a with a magnitude of 10.0 m/s2 in a direction 60.0 east of north. Figure P4.29 shows a view of the object from above. The force F2 acting on the object has a magnitude of 5.00 N and is directed north. Determine the magnitude and direction of the one other horizontal force F1 acting on the object. Figure P4.29arrow_forwardDraw a free-body diagram for the burglar, who is shown at rest while sneaking through a chimney in Figure P6.6.arrow_forwardReview. A block of mass m = 2.00 kg is released from rest at h = 0.500 m above the surface of a table, at the top of a = 30.0 incline as shown in Figure P4.53. The frictionless incline is fixed on a table of height H = 2.00 m. (a) Determine the acceleration of the block as it slides down the incline. (b) What is the velocity of the block as it leaves the incline? (c) How far from the table will the block hit the floor? (d) What time interval elapses between when the block is released and when it hits the floor? (e) Does the mass of the block affect any of the above calculations? Figure P4.53 Problems 53 and 59arrow_forward
- A ball hanging from a light string or rod can be used as an accelerometer (a device that measures acceleration) as shown in Figure P5.18. What force causes the deflection of the ball? Is the cart in the lower part of the photo an inertial reference frame? How can the balls deflection be used to find the carts acceleration? In which direction is the cart accelerating? Explain your answers.arrow_forwardIf your car is stuck in the mud and you don’t have a winch to pull it out, you can use a piece of rope and a tree to do the trick. First, you tie one end of the rope to your car and the other to a tree, then pull as hard as you can on the middle of the rope, as shown in P4.74a. This technique applies a force to the car much larger than the force that you can apply directly. To see why the car experiences such a large force, look at the forces acting on the center point of the rope, as shown in P4.74b. The sum of the forces is zero, thus the tension is much greater than the force you apply. It is this tension force that acts on the car and, with luck, pulls it free. Suppose your efforts work, and the car begins to move forward out of the mud. As it does so, the force of the car on the rope isA. Zero.B. Less than the force of the rope on the car.C. Equal to the force of the rope on the car.D. Greater than the force of the rope on the car.arrow_forwardIf your car is stuck in the mud and you don’t have a winch to pull it out, you can use a piece of rope and a tree to do the trick. First, you tie one end of the rope to your car and the other to a tree, then pull as hard as you can on the middle of the rope, as shown in P4.74a. This technique applies a force to the car much larger than the force that you can apply directly. To see why the car experiences such a large force, look at the forces acting on the center point of the rope, as shown in P4.74b. The sum of the forces is zero, thus the tension is much greater than the force you apply. It is this tension force that acts on the car and, with luck, pulls it free. Assume that you are pulling on the rope but the car is not moving. What is the approximate direction of the force of the mud on the car?A. North B. SouthC. East D. Westarrow_forward
- An aircraft carrier uses a device called a catapult to help accelerate jets to the speed needed for take off. The flight decks on these carriers have length d = 82 m. A jet with a mass of m = 12571 kg can be accelerated from rest to a speed of v = 49 m/s by the end of the flight deck. A.) calculate the numerical value of the magnitude of force F in newtons. B.) Wht is the numerical value of the ratio of the launch force F to the jets weight?arrow_forwardTwo objects with masses of 4.00 kg and 5.00 kg are connected by a light string that passes over a frictionless pulley as in Figure P4.34. Figure P4.34 (a) Determine the tension in the string. (b) Determine the acceleration of each object. m/s? (c) Determine the distance each object will move in the first second of motion if both objects start from rest. marrow_forwardDo F onlyarrow_forward
- Figure Q4 shows the track of a roller coaster. If the track is to be designed so that the passengers of the roller coaster do not experience a normal force equal to zero or more than 5 times their weight, determine the limiting heights h, and hc so that this does not occur. The roller coaster starts from rest at position A. pB and pc are radii of curvature of the track at locations B and C, respectively. Neglect friction.arrow_forwardTwo friends are sitting in a stationary canoe. At t = 3.0 s the person at the front tosses a sack to the person in the rear, who catches the sack 0.2 s later. Which plot given shows the velocity of the boat as a function of time? Positive velocity is forward, negative velocity is backward. Neglect any drag force on the canoe from the water.arrow_forwardA block is on a frictionless table, on earth. The block accelerates at 2.6 m/s 2 when a 70 N horizontal force is applied to it. The block and table are set up on the moon. The acceleration due to gravity at the surface of the moon is 1.62 m/s 2. The weight of the block on the moon is closest to: O 38 N O 33 N O 27 N O 22 N O 44 Narrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning