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Exploring how energy moves from one object to another through collisions and contact.
Have you ever wondered why a still soccer ball suddenly zooms away when your foot kicks it? It’s not magic—it’s a secret hand-off of power happening right before your eyes!
Energy is the 'power' that makes things move or change. One of the coolest things about energy is that it never just disappears; instead, it likes to travel! When energy moves from one object to another, we call this energy transfer. Think of it like a relay race where one runner passes a baton to the next. The first runner (the moving object) slows down or stops, while the next runner (the second object) takes the baton and starts moving fast!
Quick Check
If you push a toy car and it starts to roll, did energy move from your hand to the car?
Answer
Yes! This is an example of energy transfer from your hand to the toy.
Sometimes energy moves just because two things are touching. This is very common with heat energy. If you place a cold metal spoon into a bowl of hot soup, the spoon will eventually feel warm. The 'fast-moving' heat energy from the soup transfers into the 'slower' cold spoon. This movement happens through contact. Even rubbing your hands together creates energy transfer—the motion of your hands transfers into heat energy that warms your skin!
1. You hold a mug of warm cocoa on a cold day. 2. Your cold fingers start to feel warm. 3. The heat energy moved from the mug to your hand through contact. 4. Result: The mug loses a little heat, and your hands gain it!
What happens when a moving object hits something else? This is called a collision. During a collision, the moving object transfers its energy of motion to the object it hits. If you've ever played bowling, you've seen this! The heavy ball has lots of energy. When it hits the pins, that energy transfers into them, making them fly in different directions. Some of that energy even turns into sound energy—that's the 'CRASH' you hear!
1. Car A is moving at miles per hour. 2. Car B is sitting still. 3. Car A hits Car B (a collision). 4. Car A slows down because it gave away its energy. 5. Car B zooms forward because it received that energy!
Quick Check
When a moving object hits a still object, what usually happens to the speed of the first object?
Answer
The first object usually slows down because it transferred some of its energy to the second object.
Imagine five marbles in a straight line, all touching. If you roll a sixth marble into the end of the line, only the marble at the very other end pops out! 1. The first marble hits the line. 2. Its energy transfers through marble #2, #3, #4, and #5. 3. Since the middle marbles have no room to move, they just pass the energy along. 4. The last marble has nothing blocking it, so it uses the energy to roll away.
What is it called when energy moves from one object to another?
When a bowling ball hits pins, what happens to the energy?
True or False: Heat can move from a hot object to a cold object through touch.
Review Tomorrow
In 24 hours, try to explain to a friend what happens to the energy when a foot kicks a ball.
Practice Activity
Try this on your own: Place a metal spoon in a cup of warm water for one minute. Touch the handle. Can you feel where the energy moved?