Friction and Net Force

Forces, Friction, & Newton's Laws

use this Quizizz to study

Multiple Select

what is a force?

Select all the correct answers

• a push

• the temperature

• a pull

Multiple Choice

What is the net force?

• 10 N

• 25 N

• 0 N

Multiple Choice

What is the net force?

• 5 N right

• 10 N left

• 15 N right

Multiple Choice

What do you see in this picture?

• balanced force

• unbalanced force

Multiple Choice

What direction will this object move?

• right

• left

Multiple Choice

which option is an example of a noncontact force?

Multiple Choice

which option is an example of a contact force?

Friction

Friction is a force. It stops objects from moving.

Multiple Choice

A person having difficulty pushing a box.

What type of friction is shown in this picture?

• static friction

• sliding friction

• rolling friction

Sliding friction

The friction force works against the motion & makes it harder to move objects.

more friction = harder to move

Multiple Choice

A couch standing still in your living room.

What type of friction is shown in this picture?

• static

• sliding

• rolling

Static Friction

Static friction keeps objects in one place. The couch is staying in one place.

Multiple Choice

A snowball moving down the hill will eventually stop.

What type of friction is shown in this picture?

• static

• sliding

• rolling

Rolling Friction

Rolling friction slows down objects that are rolling across a surface.

like a wheel or a ball

Multiple Choice

How much applied force do you need in order to move this box?

The friction force is 100 N.

• 100N

• 150 N

• 50 N

If there is more friction, you will need more force to move an object!!

more friction = more force

Open Ended

Why did the person fall off the skateboard?

The person fell off the skateboard because.....

Multiple Select

What is inertia?

Select 2 answers

• objects in motion will stay in motion

• objects will spontaneously move

• objects at rest will stay at rest

The girls will keep sliding down the hill until a force stops them

maybe they will hit a snow pile and stop.

Maybe the force of friction will slow them down.

Open Ended

Which object has the most INERTIA?

(Which object would the most difficult to stop if it were moving?)

(which object would require the most force to move it?)

The airplane

an airplane has the most mass .

moe mass = more inertia

use this picture of two objects for the next two questions.

The red arrows show gravity between these two objects.

Multiple Choice

What happens to the force of gravity between two objects if they move farther apart?

• the force of gravity will increase

• the force of gravity will decrease

Gravity depends on distance

closer objects have more gravity.

objects that are farther apart have less gravity.

Multiple Choice

What happens to the force of gravity between two objects if the mass of one (or both) of the objects increases?

• the force of gravity will increase

• the force of gravity will decrease

Gravity depends on mass

more mass = more gravity

less mass = less gravity

Gravity depends on mass and distance.

Multiple Choice

Where is the most gravitational pull?

• A

• B

• C

• they are all the same

Multiple Choice

Where is the weakest (least) gravitational pull?

• A

• B

• C

• they are all the same

The closest point = more gravity.

The farther point = less gravity

Multiple Choice

what is mass?

• the weight of an object

• the amount of matter in an object

• the amount of gravity pulling down on an object

Multiple Choice

what is weight?

• the amount of gravity pulling down on an object

• the amount of matter in an object

Mass and weight are not the same

mass = kg

weight = gravity on an object

To Prove it....

Mass is the same on Earth and on Mars.

Weight is different because there is different gravity on the Earth and on Mars.

Multiple Choice

what will happen if you apply more force to the cart?

(push the cart harder)

• the cart will move faster

• the cart will catch on fire

• the speed of the cart will remain the same

More force = more acceleration

Multiple Choice

Which object will require more force to move it?

• watermelon

• apple

Mass & Force

you need to apply more force to move an object that has more mass.

Multiple Choice

which object will accelerate faster?

• ball with more mass

• ball with less mass

Multiple Choice

what is A?

• action - force

• reaction - opposite force

Multiple Choice

what is B?

• action - force

• reaction - opposite force

Open Ended

You bump your elbow on the corner of the table....

Name two forces present in this situation.

Newton's Third Law

every action has an equal and opposite reaction

Newtons' Third Law