Unit 2 Lesson 1

After walking across a carpet, a boy feels a spark between his hand and a doorknob.  If the boy’s hand is negatively charged just before he touches the doorknob, what conclusion can you draw about the particles that moved from the carpet to his hand?

• The particles that moved from the carpet were atoms. 
• The particles that moved from the carpet were electrons.
• The particles that moved from the carpet were neutrons.
• The particles that moved from the carpet were protons. 

This diagram below shows the particles that make up an atom.  Which part of an atom is positively charged?

• electron
• proton
• neutron
• both proton and neutron

What is static electricity?

• a flow of electrons
• an electrostatic discharge 
• a repelling between electrons
• a build up of electric charge on something

What effect will one positive charge have on another positive charge?

• They repel each other from a distance.
• They attract each other from a distance.
• They repel each other only when they touch.
• They attract each other only when they touch. 

We see lightning as a flash of light in the sky. Lightning can occur during rainstorms and hot summer days. Lightning is an example of what?

• electric charge 
• electric current
• static electricity
• electrostatic discharge

• The circuit lacks a power source.
• The light bulb uses the electric current. 
• The circuit is not a complete loop.
• The paper clip stops the electric current. 

Jayden wants to compare how well different materials conduct electricity. He builds a circuit and uses various objects to complete the circuit. He compares how brightly a light bulb glows using each object. The table below shows the results.  Which object is the BEST insulator of electricity?

• nail
• crayon
• eraser
• pencil lead
  

What is the main difference between an electric current and static electricity?

• Electrons in an electric current move by electrostatic discharge.
• Electric charges flow in an electric current but not in static electricity.
• Static electricity occurs in at least two objects. An electric current occurs in only one.
• Negative charges form static electricity. An electric current involves positive charges. 

Which object prevents the flow of electric current?

• salt water
• steel pan
• rubber eraser
• copper pipe

Many homes use electric ovens to cook food. What energy transformation occurs in an electric oven?

• thermal energy into light energy 
• thermal energy into electrical energy
• electrical energy into thermal energy
• electrical energy into energy of motion