Concept explainers
Predict/Calculate A light spring with a fore© constant of 13 N/m is connected to a wall and to a 1.2-kg toy bulldozer as shown in Figure 6-68. When the electric motor in the bulldozer is turned on, it stretches the spring for a distance of 0.45 m before its tread begins to slip on the floor. (a) Which coefficient of friction (static or Kinetic) can be determined from this information? Explain (b) What is the numerical value of this coefficient of friction?
Want to see the full answer?
Check out a sample textbook solutionChapter 6 Solutions
EBK PHYSICS
Additional Science Textbook Solutions
Campbell Essential Biology (7th Edition)
Microbiology: An Introduction
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
Chemistry: An Introduction to General, Organic, and Biological Chemistry (13th Edition)
Introductory Chemistry (6th Edition)
Biology: Life on Earth with Physiology (11th Edition)
- To give a pet hamster exercise, some people put the hamster in a ventilated ball andallow it roam around the house(Fig. P13.66). When a hamsteris in such a ball, it can cross atypical room in a few minutes.Estimate the total kinetic energyin the ball-hamster system. FIGURE P13.66 Problems 66 and 67arrow_forwardThe system shown in Figure P5.49 has an acceleration of magnitude 1.50 m/s2. Assume that the coefficient of kinetic friction between block and incline is the same for both inclines. Find (a) the coefficient of kinetic friction and (b) the tension in the string.arrow_forwardUnreasonable Results A mother pushes her child on a swing so that his speed is 9.00 m/s at the lowest point of his path. The swing is suspended 2.00 m above the child's center of mass. (a) What is the magnitude of the centripetal acceleration of the child at the low point? (b) What is the magnitude of the force the child exerts on the seat if his mass is 18.0 kg? (c) What is unreasonable about these results? (d) Which premises are unreasonable or inconsistent?arrow_forward
- A frictionless plane is 10.0 m long and inclined at 35.0. A sled starts at the bottom with an initial speed of 5.00 m/s up the incline. When it reaches the point at which it momentarily stops, a second sled is released from the top of this incline with an initial speed vi. Both sleds reach the bottom of the incline at the same moment. (a) Determine the distance that the first sled traveled up the incline. (b) Determine the initial speed of the second sled.arrow_forwardA uniform pole is propped between the floor and the ceiling of a room. The height of the room is 7.80 ft, and the coefficient of static friction between the pole and the ceiling is 0.576. The coefficient of static friction between the pole and the floor is greater than that between the pole and the ceiling. What is the length of the longest pole that can be propped between the floor and the ceiling?arrow_forwardTo get in shape, you head to the local gym to exercise by lifting weights. Using a lat machine (Fig. P5.48), you notice that the wire connected to the bar is run around three different pulleys and is connected to a vertical stack of weights on the other end. The weights move up and down as you pull down on the bar. Suppose you set the machine so that the weight to be lifted is 120.0 lb. When you pull down on the bar, exerting a constant force, the acceleration experienced by the weights is 0.250 m/s2. What tension must exist in the wire connecting the bar and weights under these conditions? Assume the pulleys are massless and frictionless. FIGURE P5.48arrow_forward
- A 0.500-kg potato is fired at an angle of 80.0 above the horizontal from a PVC pipe used as a “potato gun” and reaches a height of 110.0 m. (a) Neglecting air resistance, calculate the potato’s velocity when it leaves the gun. (b) The gun itself is a tube 0.430 m long. Calculate the average acceleration of the potato in the tube as it goes from zero to the velocity found in (a). (c) What is the average force on the potato in the gun? Express your answer in newtons and as a ratio to the weight of the potato.arrow_forwardReview. A force platform is a tool used to analyze the performance of athletes by measuring the vertical force the athlete exerts on the ground as a function of time. Starting from rest, a 65.0-kg athlete jumps down onto the platform from a height of 0.600 m. While she is in contact with the platform during the time interval 0t 0.800 s, the force she exerts on it is described by the function F = 9 200t 11 500 t2 where F is in newtons and t is in seconds. (a) What impulse did the athlete receive from the platform? (b) With what speed did she reach the platform? (c) With what speed did she leave it? (d) To what height did she jump upon leaving the platform?arrow_forwardv = 0 M A box of mass M = 3 kg is initially held at rest near the top of a ramp that makes an angle of 0 = 38 degrees with respect to the horizontal. The static and kinetic coefficients of friction between the box and the plane are ls = 0.58 and Hk = 0.43 respectively. When the box is released it accelerates down the ramp and is observed to have a speed Vp = 1.675 m/s when it is a distance D from its starting point. %3D 25) The total work done on the box by all forces as it slides down the ramp is Equal to zero. Greater than zero. Less than zero. 26) What is the value of D? D = 0.52 m D = 1.22 m D = 1.04 m D = 0.13 m D = 0.9 marrow_forward
- 3) A 40.0-kg child swings in a swung supported by two chains, each 3.00 m long. The tension in each chain at the lowest point is 350 N. Find (a) the child’s speed at the lowest point and (b) the force exerted by the seat on the child at the lowest point. Ignore the mass of the seat. college physics 11th edition textbook topic 7.4arrow_forwardAt what height in (A) must the wooden board be inclined such that the maximum static friction is obtained when the angle of repose is 32.4°?arrow_forward8:19 y & 9 2 • Part III. Friction 1. Click on "Friction" 2. Select the checkboxes: Forces, Sum of Forces, Values, Masses and Speed. Keep the knob that regulates the friction at the center of the scale. V Forces Sum of Forces Values Masses V Speed Friction None Lots 3. Start to push the box, increasing the force applied on the box slowly. There is a force that is opposite to the force you are applying. What is the name of the force opposing to the motion? 4. Once the box start moving, the magnitude of the resultant force increase instantaneously. How do you explain that? 5. Push the box and find the force needed to make the box to start moving. Add more mass (box, kid, man, refrigerator, basket as needed) and repeat the procedure such that you complete the table below. Hint: Weight = mass x gravity Magnitude of Normal Force = Maanitude of ||arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPhysics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- Physics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningClassical Dynamics of Particles and SystemsPhysicsISBN:9780534408961Author:Stephen T. Thornton, Jerry B. MarionPublisher:Cengage Learning