Suppose that the block now moves across the surface with constant speed under the action of a horizontal 3.0-N force. Which one of the following statements concerning this situation is false? A A) The direction of the total force that the surface exerts on the block is vertically upward B B) The block is not accelerated. C C) The net force on the block is zero newtons. D) The frictional force on the block has magnitude 3.0 N.

Suppose that the block now moves across the surface with constant speed under the action of a horizontal 3.0-N force. Which one of the following statements concerning this situation is false? A A) The direction of the total force that the surface exerts on the block is vertically upward B B) The block is not accelerated. C C) The net force on the block is zero newtons. D) The frictional force on the block has magnitude 3.0 N.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter4: Forces In One Dimension

Section: Chapter Questions

Problem 60A

See similar textbooks

Similar questions

Two teams of nine members each engage in tug-of-war. Each of the first team’s members has an average mass of 68 kg and exerts an average force of 1350 N horizontally. Each of the second team’s members has an average mass of 73 kg and exerts an average force of 1365 N horizontally. (a) What is magnitude of the acceleration of the two teams, and which team sins? (b) What is the tension in the section of rope between the teams?
In Figure OQ5.2, a locomotive has broken through the wall of a train station. During the collision, what can be said about the force exerted by the locomotive on the wall? (a) The force exerted by the locomotive on the wall was larger than the force the wall could exert on the locomotive. (b) The force exerted by the locomotive on the wall was the same in magnitude as the force exerted by the wall on the locomotive. (c) The force exerted by the locomotive on the wall was less than the force exerted by the wall on the locomotive. (d) The wall cannot be said to exert a force; after all, it broke. Figure OQ5.2
(a) Find an equation to determine the magnitude of the net force required to stop a car of mass m, given that the initial speed of the car is v0 and the stopping distance is x . (b) Find the magnitude of the net force if the mass of the car is 1050 kg, the initial speed is 40.0 km/h, and the stopping distance is 25.0 m.
An object of mass m = 1.00 kg is observed to have an acceleration a with a magnitude of 10.0 m/s2 in a direction 60.0 east of north. Figure P4.29 shows a view of the object from above. The force F2 acting on the object has a magnitude of 5.00 N and is directed north. Determine the magnitude and direction of the one other horizontal force F1 acting on the object. Figure P4.29
Suppose two children push horizontally, but in exactly opposite directions, on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N, and the mass of the third child plus wagon is 23.0 kg. (a) What is the system of interest if the acceleration of the child in the wagon is to be calculated? (b) Draw a free-body diagram, including all forces acting on the system. (c) Calculate the acceleration. (d) What would the acceleration be if friction were 15.0 N?
A block of mass 3.00 kg is pushed up against a wall by a force P that makes an angle of = 50.0 with the horizontal as shown in Figure P5.12. The coefficient of static friction between the block and the wall is 0.250. (a) Determine the possible values for the magnitude of P that allow the block to remain stationary. (b) Describe what happens if P has a larger value and what happens if it is smaller. (c) Repeat parts (a) and (b), assuming the force makes an angle of = 13.0 with the horizontal. Figure P5.12
A young woman buys an inexpensive used car for stock car racing. It can attain highway speed with an acceleration of 8.40 mi/h s. By making changes to its engine, she can increase the net horizontal force on the car by 24.0%. With much less expense, she can remove material from the body of the car to decrease its mass by 24.0%. (a) Which of these two changes, if either, will result in the greater increase in the cars acceleration? (b) If she makes both changes, what acceleration can she attain?
A 75.0-kg man stands on a bathroom scale in an elevator that accelerates from rest to 30.0 m/s in 2.00 s. (a) Calculate the scale reading in newtons and compare it with her weight. (The scale exerts an upward force on her equal to its reading.) (b) What Is unreasonable about the result? (c) Which premise is unreasonable, or which premises are inconsistent?
In Example 4.5, we pushed on two blocks on a table. Suppose three blocks are in contact with one another on a frictionless, horizontal surface as shown in Figure P4.49. A horizontal force F is applied to m1. Take m1 = 2.00 kg, m2 = 3.00 kg, m3 = 4.00 kg, and F = 18.0 N. (a) Draw a separate free-body diagram for each block. (b) Determine the acceleration of the blocks. (c) Find the resultant force on each block. (d) Find the magnitudes of the contact forces between the blocks. (e) You are working on a construction project. A coworker is nailing up plasterboard on one side of a light partition, and you are on the opposite side, providing backing by leaning against the wall with your back pushing on it. Every hammer blow makes your back sting. The supervisor helps you put a heavy block of wood between the wall and your back. Using the situation analyzed in parts (a) through (d) as a model, explain how this change works to make your job more comfortable. Figure P4.49
A crate is sitting in the center of a flatbed truck. As the truck accelerates to the east, the crate moves with it, and doesnt slide on the bed of the truck. In what direction is the friction force exerted by the bed of the truck on the crate? (a) To the west, (b) To the east, (c) There is no friction force because the crate isnt sliding.
An object of mass m is dropped from the roof of a building of height h. While the object is falling, a wind blowing parallel to the face of the building exerts a constant horizontal force F on the object. (a) How long does it take the object to strike the ground? Express the time t in terms of g and h. (b) Find an expression in terms of m and F for the acceleration ax of the object in the horizontal direction (taken as the positive x-direction). (c) How far is the object displaced horizontally before hitting the ground? Answer in terms of m, g, F, and h. (d) Find the magnitude of the objects acceleration while it is falling, using the variables F, m, and g.
(a) What is the strength of the weak nuclear force relative to the strong nuclear force? (b) What is the strength of the weak nuclear force relative to the electromagnetic force? Since the weak nuclear force acts at only very short distances, such as inside nuclei, where the strong and electromagnetic forces also act, it might seem surprising that we have any knowledge of it at all. We have such knowledge because the weak nuclear force is responsible for beta decay, a type of nuclear decay not explained by other forces.