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Inside the Machine G3 to G5 / Week 06 / Wednesday
3/6
Week 06 · Power and heat

Wednesday

Why devices get warm
// From the wall to the warm little fan
⏱ about 15 min

Wednesday: Why devices get warm

A neighbor brings a laptop wrapped in a blanket. "It was on my bed, and it got really hot," she says. "Then the game went slow."

Raven feels the air near the bottom edge. "What do you notice? It is warm here, and the blanket covered this part."

Nova circles once. "Would you like a hint? Working parts make heat. Heat has to go somewhere, or it builds up."

Work makes heat

When electricity flows through a part, some of the energy turns into heat. Every working part makes a little.

The processor works hard, so it makes a lot of heat. A busy game makes it work harder than a page of words.

Heat builds up inside a case. If it gets too high, parts can be harmed.

So a processor slows itself down when it gets too hot. That is why the game went slow.

  • Warm is normal. A device that has been working will feel warm to touch.
  • Too hot to hold comfortably is not normal. Tell a grown-up.
  • Heat leaves through vents and through the metal of the case.
  • A soft bed or sofa blocks the air, so a device can overheat.
HEAT DETECTIVE
  • Read the question.
  • Tap your answer.
Which part makes a lot of heat?
Why did the game go slow on the hot laptop?
Which surface is best for a working laptop?

Where the heat goes

Inside many laptops, a metal piece sits on the processor. The metal soaks up the heat.

A fan blows air across the metal. The warm air leaves through a vent.

The metal piece is called a heat sink. It passes the heat from the chip into the air.

Either way, heat needs a path out. Blocking the path is the problem.

Processor works
Heat builds up
Metal soaks it up
Fan moves air
Warm air leaves through a vent
StatementTrue or false?
Working parts make heat.?
A soft blanket helps a laptop stay cool.?
Devices slow down when they get too hot.?
A heat sink passes heat from a chip into the air.?
WHY THIS EXERCISEHeat is normal, but trapped heat is a problem. A clear path out keeps a device fast and safe.
Which hard-working part of a computer makes a lot of heat?
WHY THIS EXERCISEThe processor works hard, so it makes a lot of heat. Cooling is built around it.
PUT THE HOT LAPTOP FIX IN ORDER
  • ?Notice the laptop is hot and slow
  • ?Close the game for a few minutes
  • ?Test: is it cooler and faster now?
  • ?Move it to a hard, flat table
WHY THIS EXERCISEMoving a device to a hard surface is a safe fix a kid may do. So is letting it rest.
Try it
Rub your hands together fast for ten seconds. Feel the warmth.
Work makes heat in your hands, just like in a processor.
Now hold your hands still and open. Notice how fast the warmth leaves.
When electricity flows through a part, some energy turns into
A hard-working part that makes a lot of heat is the
A hot device protects itself by going

Well done! You know why a device gets warm and the safe way to cool it. Tomorrow you will meet the fan and the vents up close.

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