1/12 AMI Day Lesson

Welcome to your AMI Day Lesson!

Poll

What topics have you learned about before?

• Energy

• Work

• Waves

Complete the following questions to see what you already know!

I will be giving you hints along the way to help you!
-Ms. Duff

What is work?

In physics work has a very specific definition.

• Work is when you can measure a change done by a force.

• If you cannot measure a change then no work is done.

Multiple Choice

Which of the following sentences uses work correctly (in the Physics way)?

• Stan goes to work on the bus.

• Anne did work on the project for 5 hours.

• Joseph found that holding the banner in place is hard work.

• An engine does work on a car when the car is moving.

Multiple Choice

Work is done on an object...

• ...whenever a force acts on the object.

• ...whenever a force is perpendicular to the displacement of the object.

• ...whenever a force causes a displacement of the object.

• ...whenever a net force acts on the object.

Multiple Choice

In which of the following cases is no work done?

• A weightlifter lifts a barbell.

• A weightlifter holds a barbell overhead.

• A weightlifter slowly lowers a barbell.

• A weightlifter drops a barbell and the barbell falls to the ground.

Multiple Choice

A horse performs 15000 joules of work pulling a wagon for 20 seconds. What is the horse's power?

Hint: Use the formula.

• 750 W
• 300,000 W

• 20 W

• 15,000 W

Multiple Choice

Which of the following is the best example of work being done?

• doing homework
• lifting a box
• pushing a stationary box
• holding a box

Multiple Choice

Two people push on a wall with 100 N. The wall doesn’t move. How much work is done?

• 100J

• 100N

• 0J

• 0N

Energy Efficiency

All systems lose some energy to heat. The system releases heat due to friction in the system.

​Friction and Heat

In physics we measure efficiency by comparing how much useful energy a system outputs and how much energy we input.

Efficiency

Multiple Choice

What type of energy is the wasted energy from a light bulb?

• Thermal

• Light

• Kinetic

• Nuclear

Multiple Choice

If a roller coaster glides to a hill with 50 J of energy and 150 J of energy is lost to friction and heat. How much energy is wasted?

• 100 J

• 200 J

• 50 J

• 150 J

Multiple Choice

What does friction produce?

• light
• sound
• heat
• gravity

Multiple Choice

What reason exists for every machine being less than 100% efficient?

• wear and tear

• age of the machine

• bad design

• energy lost to friction/heat

Multiple Select

Energy cannot be created or destroyed.

• True

• False

Multiple Choice

Energy of motion is called this...

• Force

• Synthetic energy

• Frictional energy

• Kinetic Energy

Multiple Choice

When machines and people store energy to use when it is needed, this is called what?

• Platonic energy

• Potential energy

• Kinetic energy

• Symbiotic energy

Waves!

Light, sound, wifi and more travel in waves.
Frequency measures how often a wave repeats.
Wavelength measures how long a wave is.

Multiple Choice

Which wave in the diagram has the greatest frequency?

• 1
• 2
• 3
• 4

Multiple Choice

What type of interference is represented in this diagram?

• Constructive

• Destructive

Multiple Choice

What type of interference is represented in the diagram?

• Constructive

• Destructive

Multiple Choice

Sound waves in musical instruments or tubes create waves that add together and create louder sounds. What type of interference is this?

• Constructive

• Destructive

Multiple Choice

What type of interference do noise cancelling headphones use?

• Constructive Interference

• Destructive Interference

Multiple Choice

A wave with a large wavelength will have a ______ frequency and _____ energy

• high, low

• high, high

• low, high

• low, low

Multiple Choice

What is the speed of light?

• 3.0x10⁸ ms

• 3.0x10⁸ m/s

• 6.626x10^-34 Js

• 6.626x10^-34 J/s

Multiple Choice

The distance from one point to the next corresponding point on a wave is called the ________________.

• waveform
• peak
• amplitude
• wavelength

Multiple Choice

High frequency waves have _________ wavelength.

• varying
• high
• the same
• low

Multiple Choice

Which wave in the diagram has the greatest wavelength?

• 1
• 2
• 3
• 4

Multiple Choice

Which letter(s) represent the wavelength?

• A & B

• B & D

• B & F

• C & E

The end!
We will be learning more about these topics in the next month or so! I hope you stay warm and safe today!