Quiz about Intro to forces

Question 1

What is gravity?

Accepted Answer

a noncontact force

Answer

a frictional force

Answer

a contact force

Answer

a magnetic force

Question 2

Which of these is considered a contact force?

Accepted Answer

the friction between an object and air

Answer

the force between two charged particles

Answer

the gravitational pull of a planet

Answer

the force between two magnets

Question 3

A box has two forces acting on it. Once force is 100 N upward. Another force is 50 N downward. What is the net force of the box?

Accepted Answer

50 N upward

Answer

50 N downward

Answer

100 N upward

Answer

100 N downward

Question 4

Melanie watched the path a baseball followed after a pitcher threw it. She noticed that the ball traveled horizontally away from the pitcher as well as downward toward the ground. What force caused the ball to accelerate in the downward direction when it was thrown?

Accepted Answer

gravitational force

Answer

applied force

Answer

air resistance

Answer

electrical force

Question 5

Why are some forces considered to be noncontact forces?

Accepted Answer

Objects do not have to touch each other to experience a force.

Answer

Objects push each other apart to increase the distance between them.

Answer

Objects must be large in size in order to exert a force that is strong enough to notice.

Answer

Objects must be far apart in order to exert a force.

Question 6

Why is the friction force considered to be a contact force?

Accepted Answer

Friction is produced when objects slide past one another.

Answer

Friction affects only solid objects.

Answer

Friction always acts in the same direction.

Answer

Friction acts in a direction opposite to the direction of an object's motion.

Question 7

Why is the magnetic force considered to be a noncontact force?

Accepted Answer

Magnets do not have to touch each other to experience a force.

Answer

Magnets must be large in size in order to exert a force that is strong enough to notice.

Answer

Magnets push each other apart to increase the distance between them.

Answer

Magnets must be far apart in order to exert a force.

Question 8

The diagram shows the forces acting on a box. What is the the vertical net force (up and down)?

Accepted Answer

0 N no movement

Answer

50 N up

Answer

50 N down

Answer

0 N down

Question 9

The diagram shows the forces acting on a box. What is the the horizontal net force (left and right)?

Accepted Answer

50 N right

Answer

50 N left

Answer

0 N no movement

Answer

150 right

Question 10

The diagram shows the forces acting on a box. Predict how the box will move.

Accepted Answer

only right

Answer

up and left

Answer

down and left

Answer

only left

Question 11

Sean is moving heavy furniture by sliding it across the floor. He puts a blanket underneath the furniture. Why did this help him?

Accepted Answer

The friction is smaller between the blanket and the floor than between the furniture and the floor.

Answer

The friction is larger between the blanket and the floor than between the furniture and the floor.

Answer

The blanket protects the side of the furniture from bumping against the wall.

Answer

The blanket reduces the gravitational force between the furniture and the floor.

Question 12

In which situation is it better to have

low friction?

Accepted Answer

a hockey puck slides toward the goal

Answer

a skydiver uses a parachute

Answer

a student walks down a hallway

Answer

a ladder leans against the wall

Question 13

Planets A and B are both the same size, but planet B has three times the mass of planet A. How does the weight of an object compare on the two planets?

Accepted Answer

The weight of an object is three times larger on planet B.

Answer

The weight of an object will depend on more factors than just the weight and size of the planet.

Answer

The weight of an object is three times larger on planet A.

Answer

The weight of an object is the same on

both planets.

Intro to forces

13 questions