Forces Day 6 - Newton's Second Law

Newton's Second Law

How much force do we need?

Review - Newton's First Law

• Inertia means an object will keep doing what it was doing before.

• An object at rest will stay at rest.

• An object in motion will stay in motion, in a constant speed and direction.

• Unless acted upon by an UNbalanced force.

Multiple Choice

Newton's first law is also called the Law of ___.

• Forces

• Inertia

• the Land

Multiple Choice

___ means an object will keep doing what it was doing.

• Friction

• Gravity

• Inertia

Multiple Choice

Because a still object has inertia, we need ____ to make it move.

• An unbalanced force

• A balanced force

• To convince it to move

Multiple Choice

What kind of forces can change the motion of an object?

• Balanced forces

• Unbalanced forces

Multiple Choice

An unbalanced force is needed to make an object ___.

• Speed up

• Slow down

• Change direction

• All of these

Multiple Choice

If the net force = 0 N, motion ____.

• Will stop

• Will not change

Dropdown

An object at rest will stay ​

Select answer

, but an object in motion will stay ​

Select answer

, unless acted upon by ​ ​

Select answer

.

Velocity

• Velocity is the Science word for speed in a given direction.

• 50 mph east

• 10 m/s left

• 15 ft/hr up

Multiple Choice

____ is speed in a given direction.

• Force

• Acceleration

• Velocity

Multiple Choice

We can change speed into velocity by naming the ____.

• Force

• Direction

• Age

Multiple Choice

Which one is a velocity?

• 5 mph

• 10 m/s east

• 7 ft/min.

Multiple Choice

Which one is a velocity?

• 5 mph down

• 10 m/s

• 7 ft/min.

Multiple Choice

30 mph west describes an object's ____

• Speed

• Velocity

• Acceleration

Categorize

Options (18)

5 mph

5 mph left

7 inches per second

7 inches per second down

3 yards per minute

3 yards per minute west

10 km/h

15 miles per hour

20 meters per second

12 feet per minute

10 km/h north

15 miles per hour east

20 meters per second up

12 feet per minute forward

Describe ONLY how fast

Describes how fast and what direction

Fake News

Not Quite!

Organize these options into the right categories

Speed

Velocity

Fake News

Not Quite!

Acceleration

• Acceleration is the science word for a change in velocity.

  • Speeding Up

  • Slowing Down

  • Changing Direction

• Acceleration always requires an unbalanced force.

Multiple Choice

____ means to speed up, slow down, or change direction.

• Force

• Velocity

• Acceleration

Multiple Choice

Acceleration means to ____, slow down, or change direction.

• Speed Up

• Turn Left

• Spin

Multiple Choice

Acceleration means to speed up, ____, or change direction.

• Force

• Velocity

• Slow Down

Multiple Choice

Acceleration means to speed up, slow down, or ____.

• Cool down

• Change direction

• Warm up

Open Ended

"Acceleration means to ____, ____, or ____."

Multiple Choice

Acceleration requires an ____ force.

• Balanced

• Unbalanced

Newton's Second Law

• Force = Mass X Acceleration

• The more force you apply to an object, the more its motion will change.

Multiple Choice

The more force you apply to an object, ____.

• The more it will accelerate

• The less it will accelerate

Multiple Choice

Which one will push an object farther?

• A 50 N force

• A 5 N force

Multiple Choice

Who will probably kick a ball farther?

• A child

• A professional soccer player

Multiple Choice

Which one will stop a car faster?

• Applying 10 N to the brakes

• Applying 3 N to the brakes

Multiple Choice

How can you make a swing go higher?

• Apply more force

• Apply less force

Newton's Second Law

• Force = Mass X Acceleration

• The more mass an object has, the more force you need to move it.

Multiple Choice

Which cart needs more force to move?

• The empty cart

• The full cart

Multiple Choice

Why does the full cart need more force?

• It has more volume

• It has more mass

Multiple Choice

You push a scooter and a truck with 50 N of force. Which one moves more?

• The scooter

• The truck

Multiple Choice

A train and a bicycle are about to collide.

Which one will be easier to turn?

• The train

• The bicycle

Dropdown

"On top, the mass is ​

Select answer

, so the force can move the wagon ​

Select answer

.

On the bottom, the mass is ​

Select answer

, so the force can move the wagon ​

Select answer

.

Multiple Choice

You are riding your bicycle and applying 25 N to move at a constant speed.

Your friend jumps on the back. What happens next?

• The bke speeds up

• The bike slows down

• The bike keeps the same speed

Open Ended

You are pulling a full wagon at a constant speed.

The package on the back falls off.

"I predict the wagon will ____ because ______."

Connecting Newton's Laws

• Inertia means that an object will keep doing what it was doing.

• As mass increases, inertia increases.

• This is why we need more force to make an object with more mass move - it has more inertia.

Multiple Choice

____ means an object will keep doing what it was doing.

• Force

• Acceleration

• Inertia

Multiple Choice

As mass increases, inertia ____.

• Increases

• Decreases

• Stays the same

Multiple Choice

Objects with more mass take more force to move because they have ____.

• More inertia

• Less inertia

• More stubbornness

Open Ended

You are in a competition to see who can kick the ball the farthest.

You are given a choice between the soccer ball and the bowling ball.

"I would choose the ____ ball because ______."