Free Practice Quiz Question List

4 - Newton’s Laws of Motion Online Quiz Questions

Use this free practice quiz with 20 questions to review 4 - Newton’s Laws of Motion, test your knowledge, and prepare for your next test or exam.

20 questions

Choose one

1 point

Which quantity determines an object’s acceleration according to Newton’s second law?

A
The largest individual force acting on the object
B
The vector sum of all external forces acting on the object
C
The force that points in the direction of the object’s velocity
D
The sum of only the contact forces acting on the object

True or false

1 point

True or false: An object can be in equilibrium while several nonzero forces act on it.

A
True
B
False

Written response

1 point

A $5.0\ \text{kg}$ object is near Earth’s surface, where $g=9.8\ \text{m/s}^2$ . What is the magnitude of its weight?

Fill in the blank

1 point

Newton’s third-law force pair always acts on .

Choose one

1 point

Which statement correctly describes the normal force exerted by a surface on an object?

A
A force parallel to the surface that opposes sliding
B
A long-range gravitational force exerted by Earth
C
A contact force perpendicular to the surface
D
A force that always has magnitude $mg$

Choose all

1 point

Which statements describe every Newton’s third-law force pair? Select all correct choices.

A
The forces are the same type of interaction.
B
The forces have equal magnitudes.
C
The forces act on the same object.
D
The forces act in opposite directions.
E
The forces occur simultaneously.

True or false

1 point

True or false: Whenever an object is at rest on a rough surface, the static friction force must have magnitude $\mu_sN$ .

A
True
B
False

Written response

1 point

A block slides down a frictionless incline at an angle of $30^\circ$ to the horizontal. Using $g=9.8\ \text{m/s}^2$ , what is the magnitude of its acceleration parallel to the incline?

Fill in the blank

1 point

For two surfaces that are sliding relative to each other, the approximate friction force is called and has magnitude $f_k=\mu_kN$ .

Choose all

1 point

A block on a frictionless table is connected by an ideal rope over a frictionless pulley to a hanging block. Which statements are valid? Select all correct choices.

A
An ideal massless rope over a frictionless pulley has the same tension throughout.
B
Connected objects joined by an inextensible rope share the same acceleration magnitude.
C
The tension must always equal the weight of every connected object.
D
Each object still requires its own free-body diagram when analyzed separately.
E
The forces on the connected objects must be identical.

Choose one

1 point

A $60\ \text{kg}$ person stands on a scale in an elevator accelerating upward at $2.0\ \text{m/s}^2$ . Using $g=9.8\ \text{m/s}^2$ , what scale reading should the person observe?

A
468 N
B
588 N
C
708 N
D
720 N

Open ended

1 point

A box is pulled to the right across a rough horizontal floor and slides at constant height. Describe its free-body diagram and derive an expression for its horizontal acceleration in terms of $F_{\text{app}}$ , $\mu_k$ , $m$ , and $g$ .

Choose one

1 point

What does the term “centripetal force” represent in an object’s circular motion?

A
A new force that exists only during circular motion
B
The net inward force required for circular motion
C
A force that always points in the direction of velocity
D
The outward force that balances gravity

Choose one

1 point

A $2.0\ \text{kg}$ object experiences a $10\ \text{N}$ force to the right, a $6\ \text{N}$ force to the left, a $3\ \text{N}$ force upward, and a $3\ \text{N}$ force downward. What is the object’s acceleration?

A
$2\ \text{m/s}^2$ to the left
B
$2\ \text{m/s}^2$ to the right
C
$8\ \text{m/s}^2$ to the right
D
$4\ \text{m/s}^2$ upward

True or false

1 point

True or false: A free-body diagram for a selected object should include that object’s velocity and acceleration vectors as forces.

A
True
B
False

Choose one

1 point

A $4.0\ \text{kg}$ block rests on a frictionless incline that makes an angle of $30^\circ$ with the horizontal. If the block has no acceleration perpendicular to the incline, what is the normal force? Use $g=9.8\ \text{m/s}^2$ .

A
$19.6\ \text{N}$
B
$39.2\ \text{N}$
C
$33.9\ \text{N}$
D
$49.0\ \text{N}$

Choose one

1 point

Which pair is a Newton’s third-law pair for a book resting on a table?

A
The table’s upward normal force on the book and the book’s downward normal force on the table
B
The table’s upward normal force on the book and Earth’s downward gravitational force on the book
C
The book’s weight and the table’s upward normal force on the book
D
The book’s downward force on the table and Earth’s gravitational force on the book

Written response

1 point

A $60\ \text{kg}$ person stands on a scale in an elevator accelerating upward at $2.0\ \text{m/s}^2$ . What normal force does the scale exert on the person? Use $g=9.8\ \text{m/s}^2$ . Enter the value in newtons.

Written response

1 point

An ideal spring has spring constant $k=200\ \text{N/m}$ and is stretched $0.15\ \text{m}$ from its relaxed position. What is the magnitude of the spring force? Enter the value in newtons.

Choose one

1 point

A $3.0\ \text{kg}$ block on a frictionless table is connected by an inextensible rope over a frictionless pulley to a hanging $2.0\ \text{kg}$ mass. What is the magnitude of their acceleration? Use $g=9.8\ \text{m/s}^2$ .

A
$1.96\ \text{m/s}^2$
B
$2.94\ \text{m/s}^2$
C
$3.92\ \text{m/s}^2$
D
$9.80\ \text{m/s}^2$