11. [/1.66 Points] SERCP11 4.7.P.056. 0/20 Submissions Used ASK YOUR TEACHER Two blocks each of mass m are fastened to the top of an elevator as in the figure. The elevator has an upward acceleration a. The strings have negligible mass. (3) Find the tensions T1 and T2 in the upper and lower strings in terms of m, a, and g. T1: T2: (b) Compare the two tensions and determine which string would break first ifa is made sufficiently large. 0 T1 will break first. 0 T2 will break first. (c) What are the tensions if the cable supporting the elevator breaks? Need Help? _ 12. [-I1.74 Points] SERCP11 4.7.P.066. 0/20 Submissions Used ASK YOUR TEACHER Two objects with masses of m1 = 2.20 kg and m2 = 7.00 kg are connected by a light string that passes over a frictionless pulley, as in the figure below. I \"'2 (a) Determine the tension in the string. (Enter the magnitude only. Due to the nature of this problem, do not use rounded intermediate values in your calculationsincluding answers submitted in WebAssign.) l: N (b) Determine the acceleration of each object. (Enter the magnitude only.) [ ] m/sZ (c) Determine the distance each object will move in the first second of motion if both objects start from rest. [:J m Need Help? ASK YOU R TEACHER A 1,5007N crate is being pushed across a level floor at a constant speed by a force E of 350 N at an angle of 20.0 below the horizontal, as shown in the figure a below. t o 322;__ 400 7. [I1.66 Points] SERCP11 4.3.P.023. 0/20 Submissions Used (a) What is the coefficient of kinetic friction between the crate and the floor? (Enter your answer to at least three decimal places.) (b) If the 350-N force is Instead pulling the block at an angle of 20.0 above the horizontal, as shown In the gure b, what will be the acceleration of the crate? Assume that the coefficient of friction is the same as that found in part (a). m/s2 Need Help? SERCP11 4.4.P.027. 0/20 Submissions Used ASK YOU R TEACHER A horse is harnessed to a sled having a mass of 206 kg, including supplies. The horse must exert a force exceeding 1170 N at an angle of 383 (above the horizontal) in order to get the sled moving. Treat the sled as a point particle. (3) Calculate the normal force (in N) on the sled when the magnitude of the applied force is 1170 N. (Enter the magnitude.) :] N (b) Find the coefficient of static friction between the sled and the ground beneath it. C] (c) Find the static friction force (in N) when the horse is exerting a force of 5.85 x 102 N on the sled at the same angle. (Enter the magnitude.) [ ]\" 8. [I1 .66 Points] 4. [-/1.66 Points] DETAILS SERCP11 4.2.P.012. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER Two forces are applied to a car in an effort to move it, as shown in the figure below. (Let F, = 410 N and F2 = 350 N. Assume up and to the right are in the positive directions. ) F 2 i (a) What is the resultant vector of these two forces? magnitude N direction to the right of the forward direction (b) If the car has a mass of 3,000 kg, what acceleration does it have? Ignore friction. m/s Need Help? Read It 5. [-/1.66 Points] DETAILS SERCP11 4.3.P.019. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER Calculate the magnitude of the normal force on a 17.7 kg block in the following circumstances. (Enter your answers in N.) HINT (a) The block is resting on a level surface. (b) The block is resting on a surface tilted up at a 35.80 angle with respect to the horizontal. N (c) The block is resting on the floor of an elevator that is accelerating downward at 2.03 m/s2. N9. [-/1.66 Points] DETAILS SERCP11 4.5.P.034. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A crate of mass m = 27 kg rides on the bed of a truck attached by a cord to the back of the cab as in the figure below. The cord can withstand a maximum tension of 59 N before breaking. Neglecting friction between the crate and truck bed, find the maximum acceleration the truck can have before the cord breaks. (Enter the magnitude of the maximum acceleration in the forward direction.) m / s 2 m Need Help? Read It 10. [-/1.66 Points] DETAILS SERCP11 4.4.P.028. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A block of mass 55.1 kg rests on a slope having an angle of elevation of 20.30. If pushing downhill on the block with a force just exceeding 182 N and parallel to the slope is sufficient to cause the block to start moving, find the coefficient of static friction. HINT Need Help? Read It Watch It1. [I1.66 Points] DETAILS SERCP11 4.2.P.003. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A 8.6 kg object undergoes an acceleration of 4.2 m/sz. (a) What is the magnitude of the resultant force acting on it? l J\" (b) If this same force is applied to a 5.2 kg object, what acceleration is produced? Ewe Need Help? 2. [I1.66 Points] DETAIIS SERCP11 4.2.P.005. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A bag of sugar weighs 2.00 lb on Earth. What would it weigh in newtons on the Moon, where the free-fall acceleration IS one-sixth that on Earth? [2\" Repeat for Neptune, where g is 1.44 times that on Earth. [:N Find the mass of the bag of sugar in kilograms at each of the three locations. :1 Moon Neptune S Need Help? _' k9 k9 kg 3. [-/1.66 Points] DETAIlj SERCP11 4.2.P.010. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A 4.0-9 bullet leaves the muzzle of a rifle with a speed of 336 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.83-m-long barrel of the rifle? [: N Need Help? __' 5. [-/1.66 Points] DETAILS SERCP11 4.3.P.019. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER Calculate the magnitude of the normal force on a 17.7 kg block in the following circumstances. (Enter your answers in N.) HINT (a) The block is resting on a level surface. N (b) The block is resting on a surface tilted up at a 35.80 angle with respect to the horizontal. IN (c) The block is resting on the floor of an elevator that is accelerating downward at 2.03 m/s2. N d) The block is on a level surface and a force of 115 N is exerted on it at an angle of 35.80 above the horizontal. N Need Help? Read It Watch It 6. [-/1.66 Points] DETAILS SERCP11 4.3.P.020. 0/20 Submissions Used MY NOTES ASK YOUR TEACHER A horizontal force of 91.7 N is applied to a 34.5 kg crate on a rough, level surface. If the crate accelerates at 1.08 m/s, what is the magnitude of the force of kinetic friction (in N) acting on the crate? HINT IN Need Help? Read It Watch It