Question 1

A factory robot drops a 10 kg computer onto a conveyor belt running at 3.1 m/s. The materials are such that μs = 0.50 and μk = 0.30 between the belt and the computer. How far is the computer dragged before it is riding smoothly on the belt?

Accepted Answer

A)  1.6 m 
B)  0.98 m 
C)  2.3 m 
D)  3.0 m

Question 2

Two weights are connected by a massless wire and pulled upward with a constant speed of 1.50 m/s by a vertical pull P. The tension in the wire is T (see figure). Which one of the following relationships between T and P must be true?

Accepted Answer

A)  T > P 
B)  T = P 
C)  P + T = 125 N 
D)  P = T + 25 N 
E)  P = T + 100 N

Question 3

A system comprising blocks, a light frictionless pulley, a frictionless incline, and connecting ropes is shown in the figure. The 9.0-kg block accelerates downward when the system is released from rest. The tension in the rope connecting the 6.0-kg block and the 4.0-kg block is closest to

Accepted Answer

A)  30 N. 
B)  33 N. 
C)  36 N. 
D)  39 N. 
E)  42 N.

Question 4

A 1520-N crate is to be held in place on a ramp that rises at 30.0° above the horizontal (see figure). The massless rope attached to the crate makes a 22.0° angle above the surface of the ramp. The coefficients of friction between the crate and the surface of the ramp are µ_k = 0.450 and µ_s = 0.650. The pulley has no appreciable mass or friction. What is the MAXIMUM weight w that can be used to hold this crate stationary on the ramp?

Accepted Answer

The answer of A 1520-N crate is to be held...

Question 5

Which one of the following free-body diagrams best represents the free-body diagram, with correct relative force magnitudes, of a person in an elevator that is traveling upward with an unchanging velocity?  f  is the force of the floor on the person and 
g is the force of gravity on the person.

Accepted Answer

A) 
 
B) 
 
C) 
 
D) 
 
E)

Question 6

A 600-kg car is going around a banked curve with a radius of 110 m at a speed of 24.5 m/s. What is the appropriate banking angle so that the car stays on its path without the assistance of friction?

Accepted Answer

A)  29.1° 
B)  13.5° 
C)  33.8° 
D)  56.2° 
E)  60.9°

Question 7

Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

Accepted Answer

A)  It takes the lighter object 5 times longer to reach the bottom of the incline than the heavier object. 
B)  It takes the lighter object 10 times longer to reach the bottom of the incline than the heavier object. 
C)  It takes the heavier object 5 times longer to reach the bottom of the incline than the lighter object. 
D)  It takes the heavier object 10 times longer to reach the bottom of the incline than the lighter object. 
E)  The two objects reach the bottom of the incline at the same time.

Question 8

A 50.0-kg block is being pulled up a 16.0° slope by a force of 250 N which is parallel to the slope. The coefficient of kinetic friction between the block and the slope is 0.200. What is the magnitude of the acceleration of the block?

Accepted Answer

A)  0.528 m/s2 
B)  0.158 m/s2 
C)  0.412 m/s2 
D)  0.983 m/s2 
E)  0.260 m/s2

Question 9

The figure shows two forces acting on an object, with magnitudes F1 = 78 N and F2 = 26 N. What third force will cause the object to be in equilibrium (acceleration equals zero)?

Accepted Answer

A)  52 N pointing down 
B)  52 N pointing up 
C)  82 N pointing down 
D)  82 N pointing up

Question 10

A new roller coaster contains a loop-the-loop in which the car and rider are completely upside down. If the radius of the loop is 13.2 m, with what minimum speed must the car traverse the loop so that the rider does not fall out while upside down at the top? Assume the rider is not strapped to the car.

Accepted Answer

A)  11.4 m/s 
B)  12.5 m/s 
C)  10.1 m/s 
D)  14.9 m/s

Question 11

You push downward on a box at an angle 25° below the horizontal with a force of 750 N. If the box is on a flat horizontal surface for which the coefficient of static friction with the box is 0.76, what is the mass of the heaviest box you will be able to move?

Accepted Answer

A)  59 kg 
B)  68 kg 
C)  54 kg 
D)  82 kg

Question 12

Three objects are connected by massless wires over a massless frictionless pulley as shown in the figure. The tension in the wire connecting the 10.0-kg and 15.0-kg objects is measured to be 133 N. What is the tension in wire A?

Accepted Answer

A)  87.5 N 
B)  245 N 
C)  280 N 
D)  333 N 
E)  517 N

Question 13

The figure shows two wires tied to a 3.3 kg sphere that revolves in a horizontal circle at constant speed. At this particular speed the tension is the SAME in both wires. What is the tension?

Accepted Answer

A)  24 N 
B)  32 N 
C)  44 N 
D)  22 N

Question 14

A 600-kg car traveling at 24.5 m/s is going around a curve having a radius of 120 m that is banked at an angle of 20°.
(a) Is the curve properly banked for the car's speed?
(b) What is the minimum coefficient of static friction required between the road and the car's tires so the car does not skid?

Accepted Answer

The answer of A 600-kg car traveling at 24.5 m/s...

Question 15

A 20.0-N box rests on a 50.0-N box on a perfectly smooth horizontal floor. When a horizontal 15.0-N pull to the right is exerted on the lower box (see figure), both boxes move together. Find the magnitude and direction of the net external force on the upper box.

Accepted Answer

The answer of A 20.0-N box rests on a 50.0-N...

Exam 5: Applying Newtons Laws

A factory robot drops a 10 kg computer onto a conveyor belt running at 3.1 m/s. The materials are such that μs = 0.50 and μk = 0.30 between the belt and the computer. How far is the computer dragged before it is riding smoothly on the belt?

Two weights are connected by a massless wire and pulled upward with a constant speed of 1.50 m/s by a vertical pull P. The tension in the wire is T (see figure) . Which one of the following relationships between T and P must be true?

A system comprising blocks, a light frictionless pulley, a frictionless incline, and connecting ropes is shown in the figure. The 9.0-kg block accelerates downward when the system is released from rest. The tension in the rope connecting the 6.0-kg block and the 4.0-kg block is closest to

Which one of the following free-body diagrams best represents the free-body diagram, with correct relative force magnitudes, of a person in an elevator that is traveling upward with an unchanging velocity? _f is the force of the floor on the person and _g is the force of gravity on the person.

A 600-kg car is going around a banked curve with a radius of 110 m at a speed of 24.5 m/s. What is the appropriate banking angle so that the car stays on its path without the assistance of friction?

Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

A 50.0-kg block is being pulled up a 16.0° slope by a force of 250 N which is parallel to the slope. The coefficient of kinetic friction between the block and the slope is 0.200. What is the magnitude of the acceleration of the block?

The figure shows two forces acting on an object, with magnitudes F₁ = 78 N and F₂ = 26 N. What third force will cause the object to be in equilibrium (acceleration equals zero) ?

You push downward on a box at an angle 25° below the horizontal with a force of 750 N. If the box is on a flat horizontal surface for which the coefficient of static friction with the box is 0.76, what is the mass of the heaviest box you will be able to move?

Three objects are connected by massless wires over a massless frictionless pulley as shown in the figure. The tension in the wire connecting the 10.0-kg and 15.0-kg objects is measured to be 133 N. What is the tension in wire A?

The figure shows two wires tied to a 3.3 kg sphere that revolves in a horizontal circle at constant speed. At this particular speed the tension is the SAME in both wires. What is the tension?

A 600-kg car traveling at 24.5 m/s is going around a curve having a radius of 120 m that is banked at an angle of 20°. (a) Is the curve properly banked for the car's speed? (b) What is the minimum coefficient of static friction required between the road and the car's tires so the car does not skid?

A 20.0-N box rests on a 50.0-N box on a perfectly smooth horizontal floor. When a horizontal 15.0-N pull to the right is exerted on the lower box (see figure), both boxes move together. Find the magnitude and direction of the net external force on the upper box.

Exam 5: Applying Newtons Laws

A factory robot drops a 10 kg computer onto a conveyor belt running at 3.1 m/s. The materials are such that μs = 0.50 and μk = 0.30 between the belt and the computer. How far is the computer dragged before it is riding smoothly on the belt?

Two weights are connected by a massless wire and pulled upward with a constant speed of 1.50 m/s by a vertical pull P. The tension in the wire is T (see figure) . Which one of the following relationships between T and P must be true?

A system comprising blocks, a light frictionless pulley, a frictionless incline, and connecting ropes is shown in the figure. The 9.0-kg block accelerates downward when the system is released from rest. The tension in the rope connecting the 6.0-kg block and the 4.0-kg block is closest to

Which one of the following free-body diagrams best represents the free-body diagram, with correct relative force magnitudes, of a person in an elevator that is traveling upward with an unchanging velocity? f is the force of the floor on the person and g is the force of gravity on the person.

A 600-kg car is going around a banked curve with a radius of 110 m at a speed of 24.5 m/s. What is the appropriate banking angle so that the car stays on its path without the assistance of friction?

Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

A 50.0-kg block is being pulled up a 16.0° slope by a force of 250 N which is parallel to the slope. The coefficient of kinetic friction between the block and the slope is 0.200. What is the magnitude of the acceleration of the block?

The figure shows two forces acting on an object, with magnitudes F1 = 78 N and F2 = 26 N. What third force will cause the object to be in equilibrium (acceleration equals zero) ?

You push downward on a box at an angle 25° below the horizontal with a force of 750 N. If the box is on a flat horizontal surface for which the coefficient of static friction with the box is 0.76, what is the mass of the heaviest box you will be able to move?

Three objects are connected by massless wires over a massless frictionless pulley as shown in the figure. The tension in the wire connecting the 10.0-kg and 15.0-kg objects is measured to be 133 N. What is the tension in wire A?

The figure shows two wires tied to a 3.3 kg sphere that revolves in a horizontal circle at constant speed. At this particular speed the tension is the SAME in both wires. What is the tension?

A 20.0-N box rests on a 50.0-N box on a perfectly smooth horizontal floor. When a horizontal 15.0-N pull to the right is exerted on the lower box (see figure), both boxes move together. Find the magnitude and direction of the net external force on the upper box.

Which one of the following free-body diagrams best represents the free-body diagram, with correct relative force magnitudes, of a person in an elevator that is traveling upward with an unchanging velocity? _f is the force of the floor on the person and _g is the force of gravity on the person.

The figure shows two forces acting on an object, with magnitudes F₁ = 78 N and F₂ = 26 N. What third force will cause the object to be in equilibrium (acceleration equals zero) ?