The three diagrams below show a block of mass m being pulled or pushed at constant acceleration along a table with a force F. The coefficient of kinetic friction is u. What is the magnitude of the friction force in each case? Give your answer in terms of the pushing force F, m, µ, and the angle 0. (i) (ii) (iii) case (i) fk = case (ii) fk = case (iii) fk =

The three diagrams below show a block of mass m being pulled or pushed at constant acceleration along a table with a force F. The coefficient of kinetic friction is u. What is the magnitude of the friction force in each case? Give your answer in terms of the pushing force F, m, µ, and the angle 0. (i) (ii) (iii) case (i) fk = case (ii) fk = case (iii) fk =

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter4: The Laws Of Motion

Section: Chapter Questions

Problem 14CQ: Give reasons for the answers to each of the following questions: (a) Can a normal force be...

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A particle’s motion is described in Cartesian coordinates by the following equations: x(t) = sin(t), y(t) = cos(t), z(t) = (2t + e^(−t) ) The units for position are given in meters. The particle has a mass of 5 kg. What is the magnitude of the net force acting on the particle at the instant t = 1 sec?
In the figure, a slab of mass m1 = 40 kg rests on a frictionless floor, and a block of mass m2 = 10 kg rests on top of the slab. Between block and slab, the coefficient of static friction is 0.60, and the coefficient of kinetic friction is 0.40. A horizontal force F→ of magnitude 104 N begins to pull directly on the block, as shown. In unit-vector notation, what are the resulting accelerations of (a) the block and (b) the slab?
According to a simplified model of a mammalian heart, at each pulse, approximately 20 g of blood is accelerated from 0.26 m/s to 0.35 m/s during a period of 0.10 s. What is the magnitude of the force exerted by the heart muscle? Express your answer to two significant figures and include the appropriate units. F= ______ units I got 0.02N but it is wrong.
In the arrangement shown in the figure, friction exists only on the horizontal table where the body of mass m = 7 kg is located. The mass of the thread and the pulley can be neglected, m1 = 2 kg, m2 = 4 kg. a) At least how large should the coefficient of static friction be if the system starts to move?b) Now let the coefficient of friction be µ = 0.4. Calculate the forces in the parts of the thread and the acceleration of the bodies.
A block with mass m1 = 9.2 kg rests on the surface of a horizontal table which has a coefficient of kinetic friction of μk = 0.58. A second block with a mass m2 = 10.8 kg is connected to the first by an ideal string passing over an ideal pulley such that the second block is suspended vertically. The second block is released from rest, and motion occurs. Using the variable T to represent tension, write an expression for the sum of the forces in the y-direction, ΣFy, for block 2. Using the variable T to represent tension, write an expression for the sum of the forces in the x-direction, ΣFx for block 1. Block 1 accelerates along the tabletop, in the horizontal direction, while block 2 moves vertically. With the coordinate system provided in the drawing, we may write a⃗ 1=a1i^a→1=a1i^ and a⃗ 2=a2y^a→2=a2y^. Write an expression that relates the vertical component of the acceleration of block 2 to the horizontal component of the acceleration of block 1. Write an expression using the…
A block with mass m1 = 9.2 kg rests on the surface of a horizontal table which has a coefficient of kinetic friction of μk = 0.58. A second block with a mass m2 = 10.8 kg is connected to the first by an ideal string passing over an ideal pulley such that the second block is suspended vertically. The second block is released from rest, and motion occurs. Using the variable T to represent tension, write an expression for the sum of the forces in the y-direction, ΣFy, for block 2. Using the variable T to represent tension, write an expression for the sum of the forces in the x-direction, ΣFx for block 1. Block 1 accelerates along the tabletop, in the horizontal direction, while block 2 moves vertically. With the coordinate system provided in the drawing, we may write a⃗ 1=a1i^a→1=a1i^ and a⃗ 2=a2y^a→2=a2y^. Write an expression that relates the vertical component of the acceleration of block 2 to the horizontal component of the acceleration of block 1. Write an expression using the…
A block of mass m1 is placed on top of a block of mass m2. You push the two blocks so that they move up a vertical wall, with a constant force of magnitude P directed at angle theta. The coefficient of friction between m2 and the wall is u. There is no friction between the blocks and no friction between m1 and the wall. Find the force exerted by the lower block on the upper block. The answer the book gives me is (P(cos(theta)-u*sin(theta)))/(1+(m2/m1)) I get how to get the numerator but am unsure of how the denominator answer was gotten and where gravity went in the equation
There are two forces on the 1.19 kg box in the overhead view of the figure but only one is shown. For F1 = 15.7 N, a = 14.7 m/s2, and θ = 34.1°, find the second force (a) in unit-vector notation and as (b) a magnitude and (c) a direction. (State the direction as a negative angle measured from the +x direction.)
Problem 9: A horizontal force, F1 = 95 N, and a force, F2 = 19.7 N acting at an angle of θ to the horizontal, are applied to a block of mass m = 2.1 kg. The coefficient of kinetic friction between the block and the surface is μk = 0.2. The block is moving to the right.Randomized VariablesF1 = 95 NF2 = 19.7 Nm = 2.1 kg Part (a) Solve numerically for the magnitude of the normal force, FN in Newtons, that acts on the block if θ = 30°. Part (b) Solve numerically for the magnitude of acceleration of the block, a in m/s2, if θ = 30°. SO FOR A I GOT 10.73 AND IT WAS WRONG AND FOR B I GOT 52.34 WHAT AM I DOING WRONG??????///
A block with a mass of m = 46 kg rests on a frictionless surface and is subject to two forces acting on it. The first force is directed in the negative x-direction with a magnitude of F1 = 10.5 N. The second has a magnitude of F2 = 23.5 N and acts on the body at an angle θ = 23° measured from horizontal, as shown. a) Write an expression for the component of net force, Fnet,x, in the x-direction, in terms of the variables given in the problem statement. b)Write an expression for the magnitude of the normal force, FN, acting on the block, in terms of F2 and the other variables of the problem. Assume that the surface it rests on is rigid. c)Find the block's acceleration in the x-direction, ax, in meters per second squared.
A block with a mass of m = 46 kg rests on a frictionless surface and is subject to two forces acting on it. The first force is directed in the negative x-direction with a magnitude of F1 = 10.5 N. The second has a magnitude of F2 = 23.5 N and acts on the body at an angle θ = 23° measured from horizontal, as shown. a)Write an expression for the component of net force, Fnet,x, in the x-direction, in terms of the variables given in the problem statement. b)Write an expression for the magnitude of the normal force, FN, acting on the block, in terms of F2 and the other variables of the problem. Assume that the surface it rests on is rigid.
Give reasons for the answers to each of the following questions: (a) Can a normal force be horizontal? (b) Can a normal force be directed vertically downward? (c) Consider a tennis ball in contact with a stationary floor and with nothing else. Can the normal force be different in magnitude from the gravitational force exerted on the ball? (d) Can the force exerted by the floor on the ball be different in magnitude from the force the ball exerts on the floor?