The sled in Figure 4.2 is stuck in the snow. A child pulls on the rope and finds that the sled just barely begins to move when he pulls with a force of 25 N, with the rope at an angle of 30° with respect to the horizontal, (a) Sketch the sled and all the forces acting on it. Also choose a coordinate system, (b) Determine the components of all the forces on the sled along the coordinate axes. (c) Write the conditions for static equilibrium along your two coordinate directions. (d) If the sled has a mass of 12 kg, what is the coefficient of friction between the sled and the snow? (e) Is this the coefficient of static friction or the coefficient of kinetic friction? (f) If the child continues to pull on the sled and it has an acceleration of 0.30 m/s2, find the coefficient of kinetic friction between the sled and the snow.
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College Physics, Volume 1
- Two crates connected by a rope lie on a horizontal surface (Figure 1). Crate A has mass mA and crate B has mass mB. The coefficient of kinetic friction between each crate and the surface is μk. The crates are pulled to the right at constant velocity by a horizontal force F. In terms of mA, mB, and μk, calculate the magnitude of the force F. Express your answer in terms of some or all of the variables mA, mB, μk, and acceleration due to gravity g. In terms of mA, mB, and μk, calculate the tension in the rope connecting the blocks. Include the free-body diagram or diagrams you used to determine each answer.arrow_forwardA 1160 Kg car is being pulled up a frictionless ramp at a constant speed as shown. The cable makes an angle of 31 degrees above the surface of the ramp, and the ramp itself rises at 25 degrees above the horizontal. Draw all the required force vectors with their tails starting at the black dot on the front bumper showing the location and orientation of the vectors. Find the tension in the cable in Newtons. How hard does the surface of the ramp push on the car (in Newtons)?arrow_forwardHi, I need help with part d of this question. Thanks.arrow_forward
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- University Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University