Concept explainers
You have been hired as an expert witness in the case of a factory owner suing a demolition company. The particular case involves a smokestack at a factory being demolished. In order to save money, the factory owner wanted to move the smokestack to a nearby factory that was being built. The demolition company guaranteed to deliver the undamaged smokestack to the new factory by toppling the smokestack freely onto a huge cushioned platform lying on the ground. The then-horizontal smokestack would have been loaded onto a long truck rig for transport to the new factory. However, as the smokestack toppled, it broke apart at a point along its length. The factory owner is blaming the demolition company for the destruction of his smokestack. The demolition company is claiming that there was a defect in the smokestack and that is the reason for its destruction. What advice do you give the attorney who is handling the case on the side of the factory owner?
Want to see the full answer?
Check out a sample textbook solutionChapter 10 Solutions
Physics for Scientists and Engineers
- You are working in an ice skating rink and have been asked to hang a new banner on the wall. Your friend is helping you so that the ladder does not collapse by exerting a force FAL at an angle ϕ relative to the horizontal. The ladder has a length L and makes an angle of θ with respect to the vertical wall. You have a mass, mY, and are a horizontal distance x from the wall. The ladder has a mass of mL. Because the wall is slick, and the ice on the floor is slick, the frictional forces acting on the ladder are negligible. Find a formula for the magnitude of the force that your friend must exert to keep the ladder from falling, in terms of the following variables: x,L,mY,mL,θ,ϕ. Then use the following values to get a number for the magnitude of FAL θ = 34.4 degreesϕ = 26.144 degreesx = 1.612 metersL = 6.2 metersmY = 98.0 kgmL = 32.34 kgarrow_forwardAn airplane of mass 3.60 × 105 kg experienced a problem with all its tires when it was about to touch down at a runway of an airport. The tires were deadlocked and not able to roll. The airplane began to skid once it touched down and left behind a 728 m long skid mark on the runway before it came to a stop. Even though everyone on the airplane was safe, the pilot was accused of failing to land the airplane within the allowable speed limit of 80.0 m/s and his pilot license was suspended. Given that the coefficient of kinetic friction between the tires and runway was 0.496. (i) Determine the work done by friction on the tires.(ii) Use the Work-Energy Theorem to evaluate if the suspension of the pilot’s license should be revoked. #This is an exercise question, please help. Thank You.arrow_forwardA refrigerator is at rest on a level floor. Attempting to slide it across the floor, you exert a horizontal pushing force P at a height y above the floor, as in the figure. If y is too large, the refrigerator will tip instead of sliding. Find the largest value of y that makes the refrigerator slide without tipping if its mass is M = 119 kg, its center of mass is located where d = 0.49 m and h = 1.05 m, and the coefficient of static friction between the refrigerator and the floor is μs = 0.26. [Hints: Use the equilibrium conditions to place the refrigerator on the verge of both sliding and tipping (but not doing either). When the refrigerator is on the verge of tipping, the normal force will act at its lower front corner.] y = P Y m M cm- h ←d→arrow_forward
- A 1520-N crate is to be held in place on a ramp that rises at 30.0° above the horizontal (see figure). The massless rope attached to the crate makes a 22.0° angle above the surface of the ramp. The coefficients of friction between the crate and the surface of the ramp are uk = 0.450 and us = 0.650. The pulley has no appreciable mass or friction. What is the MAXIMUM weight w that can be used to hold this crate stationary on the ramp? w = ? Crate 22.0 Ramp 30,0arrow_forwardYou are a bully. You pin a 48 kg dweeb to a wall so that his feet aren't touching the ground. Your arm is extended so that it makes an angle 28 degrees with the horizontal. The dweeb's back is so sweaty with fear that there is no friction between his back and the wall. What is the magnitude of the force , in N, you must apply to keep the dweeb in equilibrium? (Use g = 10 m/s2) This scenario is represented schematically below. Unfortunately for you, years later the dweeb is your boss and he makes your life miserable. (Please answer to the fourth decimal place - i.e 12.3445)arrow_forwardWhile working on the roof of your house, you place your toolbox on the top of the roof. The roof is pitched such that it rises 6 inches for every 12 inches of horizontal run. As you turn to go down the ladder, you accidentally knock into the toolbox. The box slips down the roof and lands on the ground below approximately 3.5 ft from the house. If the weight of the toolbox is 5 lb, the roof height is 9 ft, and the total house height is 30 ft, what is the coefficient of kinetic friction between the toolbox and the roof?arrow_forward
- A small block sits at one end of a flat board that is 4.00 m long. The coefficients of friction between the block and the board are μs= 0.450 and μ = 0.400. The end of the board where the block sits is slowly raised until the angle the board makes with the horizontal is α0, and then the block starts to slide down the board. If the angle is kept equal to α0 as the block slides, what is the speed of the block when it reaches the bottom of the board? Express your answer with the appropriate units.arrow_forwardYou're standing at the top of a snow-covered hill, sloped at 20.0°. The coefficient of kinetic friction between your sled and the hill is 0.534. Unfortunately, there's a running stream just at the bottom of the hill, and you don't want to get wet. If you and your sled together have a mass of 87.0 kg, with what speed should you push off with to stop just before the stream, 77.0 m down the slope?arrow_forwardLizzy is training on the trapeze when a slight accident occurs. As a result, she is now hanging from the middle of a 60 m safety rope connected to the ceiling on one end and held by a strongwoman from the circus on the other end. She has a mass of 50 kg and the part of the rope connected to the ceiling makes an angle of 55° with the vertical. The part of the rope that connects Lizzy to her fellow circus artist makes an angle of 20° above the horizontal (the strongwoman is above Lizzy). As long as Lizzy remains stationary, what is the tension in both parts of the rope?arrow_forward
- Emma and Katie are racing along in their new wagon. Upon reaching the bottom of the hill traveling at 13.2 m/s, Katie notices her teddy bear 12.0 m in front of them, panics and locks the brakes sending the wagon into a skid. If the wagon and its contents have a total mass of 1.50 x10^1 kg, and the coefficient of kinetic friction between the road and the rubber wagon tires is (0.75), by how much does the wagon miss the bear?arrow_forwardA 80.0 kg mail bag hangs by a vertical rope 3.5 m long. A postal worker then displaces the bag to a position 2.4 m sideways from its original position, always keeping the rope taut.arrow_forwardA box is given a push so that it slides across the floor. How far will it go, given that the coefficient of kinetic friction is 0.25 and the push imparts an initial speed of 3.9 m/sm/s ?arrow_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