A box with a weight of 50 N rests on a horizontal surface. A person pulls horizontally on it with a force of 10 N and it does not move. To start it moving, a second person pulls vertically upward on the box. If the coefficient of static friction is 0.4, the smallest vertical force F applied by the second person for which the box moves is: Select one: O a. 14 N O b. 4 N O c. 10 N O d. 25 N O e. 35 N

A box with a weight of 50 N rests on a horizontal surface. A person pulls horizontally on it with a force of 10 N and it does not move. To start it moving, a second person pulls vertically upward on the box. If the coefficient of static friction is 0.4, the smallest vertical force F applied by the second person for which the box moves is: Select one: O a. 14 N O b. 4 N O c. 10 N O d. 25 N O e. 35 N

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter5: Newton's Laws Of Motion

Section: Chapter Questions

Problem 72PQ: A block of ice (m = 15.0 kg) with an attached rope is at rest on a frictionless surface. You pull...

See similar textbooks

Similar questions

(a) What is the minimum force of friction required to hold the system of Figure P4.74 in equilibrium? (b) What coefficient of static friction between the 100.-N block and the table ensures equilibrium? (c) If the coefficient of kinetic friction between the 100.-N block and the table is 0.250, what hanging weight should replace the 50.0-N weight to allow the system to move at a constant speed once it is set in motion? Figure P4.74
A block of ice (m = 15.0 kg) with an attached rope is at rest on a frictionless surface. You pull the block with a horizontal force of 95.0 N for 1.54 s. a. Determine the magnitude of each force acting on the block of ice while you are pulling. b. With what speed is the ice moving after you are finished pulling? Repeat Problem 71, but this time you pull on the block at an angle of 20.0.
(a) An elevator of mass m moving upward has two forces acting on it: the upward force of tension in the cable and the downward force due to gravity. When the elevator is accelerating upward, which is greater. T or w? (b) When the elevator is moving at a constant velocity upward, which is greater. T or w2 (c) When the elevator is moving upward, but the acceleration is downward, which is greater. T or w? (d) Let the elevator have a mass of 1500 kg and an upward acceleration of 2.5 m/s2. Find T. Is your answer consistent with the answer to part (a)? (e) The elevator of part (d) now moves with a constant upward velocity of 10 m/s. Find T. Is your answer consistent with your answer to part (b)? (f) Having initially moved upward with a constant velocity, the elevator begins to accelerate downward at 1.50 m/s2. Find T Is your answer consistent with your answer to part (c)?
(a) What is the minimum force of friction required to hold the system of Figure P4.74 in equilibrium? (b) What coefficient of static friction between the 100.-N block and the table ensures equilibrium? (c) If the coefficient of kinetic friction between the 100.-N block and the table is 0.250, what hanging weight should replace the 50.0-N weight to allow the system to move at a constant speed once it is set in motion? Figure P4.74
A car of mass 875 kg is traveling 30.0 m/s when the driver applies the brakes, which lock the wheels. The car skids for 5.60 s in the positive x-direction before coming to rest. (a) What is the cars acceleration? (b) What magnitude force acted on the car during this time? (c) How far did the car travel?
(a) A cat with a mass of 850 kg in moving to the right with a constant speed of 1.44 m/s. What is the total force on the cat ? (b) What is the total force on the cat if it is moving to the left?
A bag of cement weighing 325 N hangs in equilibrium from three wires as suggested in Figure P5.33. Two of the wires make angles 1 = 60.0 and 2 = 40.0 with the horizontal. Assuming the system is in equilibrium, find the tensions T1, T2 and T3 in the wires. Figure P5.33 Problems 33 and 34.
(a) An elevator of mass m moving upward has two forces acting on it: the upward force of tension in the cable and the downward force due to gravity. When the elevator is accelerating upward, which is greater, T or w? (b) When the elevator is moving at a constant velocity upward, which is greater, T or w? (c) When the elevator is moving upward, but the acceleration is downward, which is greater, T or w? (d) Let the elevator have a mass of 1 500 kg and an upward acceleration of 2.5 m/s2. Find T. Is your answer consistent with the answer to part (a)? (e) The elevator of part (d) now moves with a constant upward velocity of 10 m/s. Find T. Is your answer consistent with your answer to part (b)? (f) Having initially moved upward with a constant velocity, the elevator begins to accelerate downward at 1.50 m/s2. Find T. Is your answer consistent with your answer to part (c)?
A 1.0 N block is pushed against the ceiling by a 3.5 N force at a 60° angle as shown in the figure. The coefficient of static friction between the block and the ceiling is 0.9. If the block is in equilibrium, what is the magnitude of the frictional force acting on the block. 60° 3.50 N O 1.75 N O 2.73 N O 3.63 N 0.9 N
e 3. Cur 7. Two students push a 260 kg piano across the floor. Kathy pushes with 280 N [forward] while Matt pushes with 340 N [forward]. The piano accelerates at 0.30 m/s² [forward]. (a) What is the coefficient of kinetic friction? (b) How long will it take the piano to stop moving after pushing it for 6.2 s from rest?
A box ( m=8.79 kg) is placed on a horizontal surface with µs=0.2. If a force of 6.9 N is pushing the box to the right but the box does not move. What is the magnitude of the static friction force ( in N) during the effect of the 6.9 N force? Select one: O A. 6.90 B. 86.14 C. 92.639 O D. 32 O E. 17.2
2 W S X 3. Four blocks, with masses m₁ = 5.90 kg, m₂ = 5.10 kg, m3 = 8.00 kg, and m4 = 7.50 kg, are pulled on a horizontal frictionless surface by a 35.00 N force that makes a 25° angle (0) with the horizontal (see figure). What is the magnitude of the tension between the m₁ and m₂ blocks? N 3 E D C 888 R F % 5 20 V T ma 6 20 MacBook Air Y m3 B 7 H 109 91100/9/1 30 U N m₂ 8 J m₁ 9 K M 16 ceiló ceiló ecilo