Question 1

The fundamental force that is the weakest of the four is

Accepted Answer

A)  strong force. 
B)  weak force. 
C)  electromagnetic force. 
D)  gravitational force. 
A)  strong force. 
B)  weak force. 
C)  electromagnetic force. 
D)  gravitational force.

Question 2

What is the gravitational force between two nuclei,each of mass 3.20 $\times$ 10-27 kg and separated by a distance of 10.6 $\times$ 10-11 m? (G = 6.67 $\times$ 10-11 N m2/kg2)

Accepted Answer

A)  6.08 $\times$ 10-45 N 
B)  6.08 $\times$ 10-44 N 
C)  6.08 $\times$ 10-43 N 
D)  6.08 $\times$ 10-42 N 
A)  6.08 $\times$ 10-45 N 
B)  6.08 $\times$ 10-44 N 
C)  6.08 $\times$ 10-43 N 
D)  6.08 $\times$ 10-42 N

Question 3

A boy with a mass of 55 kg walks into a room and sees a girl 8.0 m in front of him who has a mass of 40 kg.What is his gravitational attraction to her?

Accepted Answer

A)  2.0 $\times$ 108 N 
B)  2.3 $\times$ 10-9 N 
C)  2.2 $\times$ 10-11N 
D)  2.4 $\times$ 10-8 N 
E)  2.1 $\times$ 109 N 
A)  2.0 $\times$ 108 N 
B)  2.3 $\times$ 10-9 N 
C)  2.2 $\times$ 10-11N 
D)  2.4 $\times$ 10-8 N 
E)  2.1 $\times$ 109 N

Question 4

The static friction force on an object

Accepted Answer

A)  can never be greater than the kinetic friction force on it under the same circumstances. 
B)  can never accelerate the object. 
C)  can never be greater than the normal force on it. 
D)  can never be greater than the object's weight. 
E)  None of the choices are correct. 
A)  can never be greater than the kinetic friction force on it under the same circumstances. 
B)  can never accelerate the object. 
C)  can never be greater than the normal force on it. 
D)  can never be greater than the object's weight. 
E)  None of the choices are correct.

Question 5

Causing an object to start moving on a frictional surface requires

Accepted Answer

A)  less force than is needed to keep it moving on the surface. 
B)  the same force as is needed to keep it moving on the surface. 
C)  more force than is needed to keep it moving on the surface. 
D)  a force equal to the weight of the object. 
E)  a force opposite to the normal force. 
A)  less force than is needed to keep it moving on the surface. 
B)  the same force as is needed to keep it moving on the surface. 
C)  more force than is needed to keep it moving on the surface. 
D)  a force equal to the weight of the object. 
E)  a force opposite to the normal force.

Question 6

A sled weighs 10.0 kg It is held in place on a frictionless 20.0 degree slope by a rope attached to a stake at the top of the slope.Find the tension in the rope if it is parallel to the slope.

Accepted Answer

A)  47.9 N 
B)  37.4 N 
C)  94.1 N 
D)  33.5 N 
E)  23.8 N 
A)  47.9 N 
B)  37.4 N 
C)  94.1 N 
D)  33.5 N 
E)  23.8 N

Question 7

In the figure an airport luggage carrying train with a tractor T is pulling three luggage carts,M1,M2,and M3,with constant velocity of 4.5 m/s.If T = 300.0 kg,M1 = 200.0 kg,M2 = 100.0 kg,and M3 = 100.0 kg,and the coefficient of kinetic friction for each is 0.4000,what is the force in the connection between the tractor T and cart M1?

Accepted Answer

A)  2941 N 
B)  2744 N 
C)  1568 N 
D)  1862 N 
E)  2439 N 
A)  2941 N 
B)  2744 N 
C)  1568 N 
D)  1862 N 
E)  2439 N

Question 8

An airplane is traveling in level flight at a constant velocity.L is the lift,W is the weight,T is the thrust,and D is the drag.Which of the diagrams is the correct free body force diagram for the airplane?

Accepted Answer

A)  Figure 1 
B)  Figure 2 
C)  Figure 3 
D)  Figure 4 
E)  Figure 5 
A)  Figure 1 
B)  Figure 2 
C)  Figure 3 
D)  Figure 4 
E)  Figure 5

Question 9

Given that a force vector extends from the origin to (120 N,-60.0 N),find the direction of the vector referenced to the positive x-axis.

Accepted Answer

A)  $116^{\circ}$ 
B)  $26.6^{\circ}$ 
C)  $-26.6^{\circ}$ 
D)  $122^{\circ}$ 
A)  $116^{\circ}$ 
B)  $26.6^{\circ}$ 
C)  $-26.6^{\circ}$ 
D)  $122^{\circ}$

Question 10

Given that a vector extends from the origin to (-5.0 cm,8.0 cm),find the magnitude of the vector.

Accepted Answer

A)  9.8 cm 
B)  3.4 cm 
C)  9.4 cm 
D)  -5.6 cm 
A)  9.8 cm 
B)  3.4 cm 
C)  9.4 cm 
D)  -5.6 cm

Question 11

In order to slide a 70.0 kg box across the floor at a constant speed,you must push horizontally with a force of 351 N.What is the coefficient of kinetic friction?

Accepted Answer

A)  0.149 
B)  0.584 
C)  0.337 
D)  0.512 
E)  0.678 
A)  0.149 
B)  0.584 
C)  0.337 
D)  0.512 
E)  0.678

Question 12

What is the gravitational force between two 5.00 kg masses that are 10.0 cm apart from center to center? (G = 6.67 $\times$ 10-11 N m2/kg2)

Accepted Answer

A)  1.67 $\times$ 10-8 N 
B)  1.67 $\times$ 10-7 N 
C)  1.62 $\times$ 10-6 N 
D)  1.62 $\times$ 10-5 N 
E)  1.67 $\times$ 10-4 N 
A)  1.67 $\times$ 10-8 N 
B)  1.67 $\times$ 10-7 N 
C)  1.62 $\times$ 10-6 N 
D)  1.62 $\times$ 10-5 N 
E)  1.67 $\times$ 10-4 N

Question 13

A worker lifts a heavy load using a two-pulley system as in the figure.If the tension in the rope segment labeled A is 725 N,what are the weight of the load,and the force that the worker exerts on the rope,respectively?

Accepted Answer

A)  363 N,725 N 
B)  725 N,363 N 
C)  1450 N,725 N 
D)  1450 N,1450 N 
E)  Insufficient information is given to answer this question. 
A)  363 N,725 N 
B)  725 N,363 N 
C)  1450 N,725 N 
D)  1450 N,1450 N 
E)  Insufficient information is given to answer this question.

Question 14

An airplane is flying in horizontal flight at a constant velocity.The weight of the airplane is 40,000 N.The wings produce a lift force that is perpendicular to the wings and a drag force that is parallel to the wing.The engine produces a forward thrust force of 2,000 N.Which of the following statements is true?

Accepted Answer

A)  the lift force on the airplane is zero 
B)  the drag force on the airplane is zero 
C)  the lift force on the airplane is 42,000 N upward 
D)  the drag force on the airplane is 38,000 N downward 
E)  the drag force on the airplane is 2,000 N backward 
A)  the lift force on the airplane is zero 
B)  the drag force on the airplane is zero 
C)  the lift force on the airplane is 42,000 N upward 
D)  the drag force on the airplane is 38,000 N downward 
E)  the drag force on the airplane is 2,000 N backward

Question 15

The fundamental force that is the principal cause of what we experience as frictional forces is:

Accepted Answer

A)  gravitational force 
B)  electromagnetic force 
C)  weak force 
D)  strong force 
A)  gravitational force 
B)  electromagnetic force 
C)  weak force 
D)  strong force

Question 16

You find a coin resting on your physics book cover and notice that when you open the cover,the coin slips exactly when the cover reaches 25 degrees above the horizontal.What is the coefficient of friction between the coin and book cover?

Accepted Answer

A)  0.20 
B)  0.23 
C)  0.37 
D)  0.47 
E)  The question cannot be answered without knowing the coin's mass. 
A)  0.20 
B)  0.23 
C)  0.37 
D)  0.47 
E)  The question cannot be answered without knowing the coin's mass.

Question 17

A 120 N traffic light is located at the midpoint of a cable between two poles.The cable makes and angle of $30^{\circ}$ to the horizontal at each pole.What is the tension in the cable?

Accepted Answer

A)  60.0 N 
B)  90.0 N 
C)  140 N 
D)  110 N 
E)  120 N 
A)  60.0 N 
B)  90.0 N 
C)  140 N 
D)  110 N 
E)  120 N

Question 18

The force that holds the nucleus together is

Accepted Answer

A)  gravitational force. 
B)  electromagnetic force. 
C)  weak interaction. 
D)  strong nuclear force. 
A)  gravitational force. 
B)  electromagnetic force. 
C)  weak interaction. 
D)  strong nuclear force.

Question 19

A 755 N box rests on a floor with a coefficient of kinetic friction of 0.600 and a coefficient of static friction of 0.800.What horizontal force is required to start the box moving?

Accepted Answer

A)  755 N 
B)  453 N 
C)  254 N 
D)  653 N 
E)  604 N 
A)  755 N 
B)  453 N 
C)  254 N 
D)  653 N 
E)  604 N

Question 20

When a person stands on a scale,which of the following is not a force exerted on the scale?

Accepted Answer

A)  a contact force due to the floor 
B)  a contact force due to the person's feet 
C)  the weight of the person 
D)  the weight of the scale 
A)  a contact force due to the floor 
B)  a contact force due to the person's feet 
C)  the weight of the person 
D)  the weight of the scale

Exam 2: Force

The fundamental force that is the weakest of the four is

What is the gravitational force between two nuclei,each of mass 3.20 ×\times× 10-27 kg and separated by a distance of 10.6 ×\times× 10-11 m? (G = 6.67 ×\times× 10-11 N m2/kg2)

A boy with a mass of 55 kg walks into a room and sees a girl 8.0 m in front of him who has a mass of 40 kg.What is his gravitational attraction to her?

The static friction force on an object

Causing an object to start moving on a frictional surface requires

A sled weighs 10.0 kg It is held in place on a frictionless 20.0 degree slope by a rope attached to a stake at the top of the slope.Find the tension in the rope if it is parallel to the slope.

An airplane is traveling in level flight at a constant velocity.L is the lift,W is the weight,T is the thrust,and D is the drag.Which of the diagrams is the correct free body force diagram for the airplane?

Given that a force vector extends from the origin to (120 N,-60.0 N),find the direction of the vector referenced to the positive x-axis.

Given that a vector extends from the origin to (-5.0 cm,8.0 cm),find the magnitude of the vector.

In order to slide a 70.0 kg box across the floor at a constant speed,you must push horizontally with a force of 351 N.What is the coefficient of kinetic friction?

What is the gravitational force between two 5.00 kg masses that are 10.0 cm apart from center to center? (G = 6.67 ×\times× 10-11 N m2/kg2)

A worker lifts a heavy load using a two-pulley system as in the figure.If the tension in the rope segment labeled A is 725 N,what are the weight of the load,and the force that the worker exerts on the rope,respectively?

The fundamental force that is the principal cause of what we experience as frictional forces is:

You find a coin resting on your physics book cover and notice that when you open the cover,the coin slips exactly when the cover reaches 25 degrees above the horizontal.What is the coefficient of friction between the coin and book cover?

A 120 N traffic light is located at the midpoint of a cable between two poles.The cable makes and angle of 30∘30^{\circ}30∘ to the horizontal at each pole.What is the tension in the cable?

The force that holds the nucleus together is

A 755 N box rests on a floor with a coefficient of kinetic friction of 0.600 and a coefficient of static friction of 0.800.What horizontal force is required to start the box moving?

When a person stands on a scale,which of the following is not a force exerted on the scale?

Introduction

Acceleration and Newtons Second Law of Motion

Motion With Constant Acceleration

Circular Motion

Conservation of Energy

Linear Momentum

Torque and Angular Momentum

Fluids

Elasticity and Oscillations

Waves

Sound

Temperature and the Ideal Gas

Heat

Thermodynamics

Electric Forces and Fields

Electric Potential

Electric Current and Circuits

Magnetic Forces and Fields

Electromagnetic Induction

Alternating Current

Electromagnetic Waves

Reflection and Refraction of Light

Optical Instruments

Interference and Diffraction

Relativity

Early Quantum Physics and the Photon

Quantum Physics

Nuclear Physics

Particle Physics

Filters

What is the gravitational force between two nuclei,each of mass 3.20 $\times$ 10^-27 kg and separated by a distance of 10.6 $\times$ 10^-11 m? (G = 6.67 $\times$ 10^-11 N m²/kg²)

What is the gravitational force between two 5.00 kg masses that are 10.0 cm apart from center to center? (G = 6.67 $\times$ 10^-11 N m²/kg²)

A 120 N traffic light is located at the midpoint of a cable between two poles.The cable makes and angle of $30^{\circ}$ to the horizontal at each pole.What is the tension in the cable?