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An inventive child named Nick wants to reach an apple in a tree without climbing the tree. Sitting in a chair connected to a rope that passes over a frictionless pulley (Fig. P5.41), Nick pulls on the loose end of the rope with such a force that the spring scale reads 250 N. Nick’s true weight is 320 N, and the chair weighs 160 N. Nick’s feet are not touching the ground. (a) Draw one pair of diagrams showing the forces for Nick and the chair considered as separate systems and another diagram for Nick and the chair considered as one system. (b) Show that the acceleration of the system is upward and find its magnitude. (c) Find the force Nick exerts on the chair.
Figure P5.41 Problems 41 and 44.
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- 41. An inventive child named Nick wants to reach an apple in a tree without climbing the tree. Sitting in a chair connected to a rope that passes over a frictionless pulley (Fig. P5.41), Nick pulls on the loose end of the rope with such a force that the spring scale reads 250 N. Nick's true weight is 320 N, and the chair weighs 160 N. Nick's feet are not touch- ing the ground. (a) Draw one pair of diagrams showing the forces for Nick and the chair considered as separate systems and another diagram for Nick and the chair considered as one system. (b) Show that the acceleration of the system is upward and find its magnitude. (c) Find the force Nick exerts on the chair.arrow_forwardA woman stands on a scale while riding in an elevator. When the elevator is at rest, the scale reads 60kg. What will be the reading of the scale in kg when the elevator accelerates. (a) upward at 1.2 m/s^2. (b) downward at 1.2 m/s^2. (c) At what acceleration of the elevator would the person appear to be weightless? Draw the FBD of the problem.arrow_forwardBe sure to review Examples 5.13, 5.14, and 5.15 (Section5.3) before attempting these problems. Figure You pull on a crate using a rope as in (Figure 1), except the rope is at an angle of 20.0° above the horizontal. The weight of the crate is 325 N, and the coefficient of kinetic friction between the crate and the floor is 0.270. What must be the tension in the rope to make the crate move at a constant velocity? Express your answer with the appropriate units. T₁ = Submit Part B 0 4 Value n1 = ША Request Answer Units Value What is the normal force that the floor exerts on the crate? Express your answer with the appropriate units. @ Units ? ?arrow_forward
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- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning