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Science Launch G4 / Week 03 / Friday
5/6
Week 03 · Energy on the Move

Friday

Electric currents
// Sound, light, heat and electric currents carry energy
⏱ about 15 min

Friday: Electric currents

Rocket clicks his flashlight. Nothing. He shakes it and clicks again. Still dark.

"It is broken!" he groans. "Let's build a new one."

Raven unscrews the end. Inside, one battery has slipped away from the metal spring. "Wait. What do you notice about this gap?"

Nova shines her own light into the tube. "Here is a clue," she says. "Electricity needs a path with no breaks."

Raven pushes the battery back. Click. Light!

Energy through wires

Energy can travel through wires as an electric current. An electric current is electricity flowing.

For electricity to flow, it needs a complete path. That path is called a circuit.

A switch opens or closes the circuit. Turning a light off opens the circuit and stops the flow.

Turning it on closes the circuit. Then electricity flows through the bulb and makes light.

Electric currents can be used to make motion, sound, heat or light.

DeviceWhat the electric current makes
Fanmotion
Doorbellsound
Lamplight
Toasterheat
HOW A FLASHLIGHT LIGHTS UP
  • ?You push the switch on
  • ?The circuit is closed
  • ?Electricity flows from the battery through the bulb
  • ?The bulb makes light
WHY THIS EXERCISEClosing the circuit lets the current carry energy from the battery to the bulb.
OPEN OR CLOSED?
  • Read the question.
  • Tap your answer.
Rocket's battery slipped and left a gap. Was the circuit open or closed?
A fan uses an electric current to make ____.
WHY THIS EXERCISEElectric currents carry energy that devices turn into motion, sound, heat or light.
Safety first
Never touch or poke wall outlets or wires.
Only grown-ups plug things in and change big batteries.

Find the break

When a circuit does not work, look for a break in the path.

A loose battery, a gap or an open switch can all stop the current.

Fix the break, and the circuit is closed again.

Then electricity can flow and carry energy to the bulb.

CIRCUIT DETECTIVE
  • Read the question.
  • Tap your answer.
A flashlight switch is turned off. Is the circuit open or closed?
Which device uses electric current to make sound?
Which device uses electric current to make heat?
StatementTrue or false?
Electricity needs a complete path to flow.?
A gap in a circuit helps electricity flow.?
A switch opens and closes a circuit.?
Electric currents can make motion, sound, heat or light.?
WHY THIS EXERCISEA circuit must be complete, and a switch controls whether it is.
A complete path for electricity is a ____.
Electricity flowing through a wire is an electric ____.
On paper, sketch a flashlight circuit: battery, wire, bulb and switch. Show the path the current takes.

Awesome week, energy tracker! Tomorrow is Launch Lab: an energy hunt at home.

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