Good Morning! Good Morning! 04/21/2304/21/23 Starter: What speed do all Starter: What speed do all

Electromagnetic waves travel at?Electromagnetic waves travel at? Today we will be taking our test on Today we will be taking our test on

Waves: Sound & Light.Waves: Sound & Light. Please take out your review and study.Please take out your review and study. The test is 40 questions all multiple The test is 40 questions all multiple

choicechoice We will be using scantron sheets and We will be using scantron sheets and

you will need a #2 pencil (all 0.7mm you will need a #2 pencil (all 0.7mm mechanical pencils will work for this)mechanical pencils will work for this)

Write your name, Waves Test for the Write your name, Waves Test for the subject and the period.subject and the period.

The EssayThe Essay

Please explain why a moving object Please explain why a moving object will create a higher frequency sound will create a higher frequency sound as it comes towards you and a lower as it comes towards you and a lower frequency sound as it is going away.frequency sound as it is going away.

Answer this in paragraph form.Answer this in paragraph form.

Good Morning! Good Morning! 04/21/2304/21/23

Starter Why do you get shocked Starter Why do you get shocked when you touch metal?when you touch metal?

Today we will be learning about Today we will be learning about moving electrons and starting moving electrons and starting our unit on electricity.our unit on electricity.

Answer: It is the moving of Answer: It is the moving of electrons.electrons.

Charge!Charge!(the electrical (the electrical

kind)kind)

How do things get How do things get a charge?a charge?

Charge is created by Charge is created by an imbalance of an imbalance of electrons.electrons.

Why is it that electrons Why is it that electrons move and protons don’t?move and protons don’t?

Protons are located in the Protons are located in the nucleus of an atom (you’ll hear nucleus of an atom (you’ll hear more about this in Physical more about this in Physical Science B) Science B)

Electrons float around the Electrons float around the nucleus and are free to leave.nucleus and are free to leave.

What What happens happens

when when you you

bring bring like like

charges charges togethertogether

??

What What happens happens when you when you bring bring unlike unlike charges charges together?together?

Why does that Why does that happen?happen?

Each charged object is Each charged object is creating a electric field.creating a electric field.

What is an electric What is an electric field?field?

What happens when What happens when you bring two you bring two electric fields electric fields

together?together?

Why do you get a shock Why do you get a shock from door knobs?from door knobs?

It has to do with a build up of It has to do with a build up of electrons but it is more electrons but it is more complex than that.complex than that.

Now that you know a Now that you know a little bit about charge little bit about charge

let’s apply that let’s apply that knowledge to some knowledge to some

questions you’ve had for questions you’ve had for a while.a while.

Static Static ElectricityElectricity

Why do Why do you get you get a shock a shock when when you you touch a touch a door door knob?knob?

When When you walk you walk across across the floor the floor you you scrap scrap electrons electrons from the from the carpet.carpet.

The The Electrons Electrons are are transferretransferred to the d to the feet and feet and throughouthroughout the body.t the body.

When your When your finger finger approaches approaches the doorknob the doorknob the electrons the electrons move away move away and leave a and leave a positive positive charge.charge.

Then the electrons jump and give you a shock

Why do balloons stick Why do balloons stick to walls after you rub to walls after you rub them on your head?them on your head?

An un-An un-chargecharged d ballooballoon does n does not not attract attract hair.hair.

The The electrons electrons

on the on the balloon balloon

repel the repel the electrons in electrons in

the wall, the wall, leaving a leaving a positive positive

charge and charge and an an

attraction attraction forceforce

Now for some fun Who Now for some fun Who wants to get shocked?wants to get shocked?

First the First the VideoVideo Shock studentsShock students Let’s get some hair in the airLet’s get some hair in the air Magical Gedi Mind TrickMagical Gedi Mind Trick Light SaberLight Saber

How does a Van De Graff How does a Van De Graff generator work?generator work?

It pulls It pulls electrons electrons off of the off of the metal metal sphere and sphere and anyone who anyone who who who touches it.touches it.

Why does your hair Why does your hair stand straight up when stand straight up when you touch the Van De you touch the Van De

Graff Generator?Graff Generator?The hair is positive because The hair is positive because

the electrons have been the electrons have been pulled off of it. The charged pulled off of it. The charged hair is simply trying to get hair is simply trying to get as far apart as possible as far apart as possible because like charges repel.because like charges repel.