Understanding Energy Transfer core knowledge

Energy Transfer

• Energy causes change.
• When you push a friend on a skateboard, your motion energy transfers to them, changing them from being at rest to moving.
• Pushing your friend is an example of an energy transfer from you to your friend.

Key Vocabulary

• Energy transfer: the movement of energy from one object to another or from one place to another.

Evidence

• Evidence includes observations, information, and facts that help prove or disprove an idea.
• Scientists and engineers use evidence to explain how and why things happen and to improve solutions to problems.

Heat Energy Transfers

• Energy can move from place to place as heat.
• Pouring hot tea into a cool cup will cause the cup to get hot because the heat energy transfers from the tea to the cup and spoon.
• The heat energy causes a temperature change to the cup and spoon.
• A cup and spoon becoming hot shows that the heat in the tea transferred, moving and causing changes.
• Hot tea transfers energy through direct contact with a cup and spoon.

Energy Transfers Between Objects in Contact

• Kicking a ball transfers energy from your body to the ball, which changes its position.
• When the first ball hits a second ball, it transfers its motion energy, changing the position of the second ball.
• These changes show that energy transfers from one object to another.

Forms of Energy

• Light, heat, electricity, and sound are all forms of energy transfer that can move energy from one place to another.
• Energy can transfer between objects that touch, but light can transfer energy over long distances without contact, like from the sun.

Light Energy Transfers

• Light transfers energy from a source like a light bulb to your eyes, allowing you to see.
• Light from the sun travels approximately 150 million kilometers (93 million miles) to reach Earth and can cause a sunburn by reflecting off your skin.

Sound Energy Transfers

• Sound energy can come from objects that are not touching you but can cause changes you can hear and feel.
• Examples are hearing a horn or feeling a push from the sound of a firework, which shows an energy transfer happened.

Electricity Transfers Electrical Energy

• Adding electrical energy to a light bulb lights it up, changing a room from dark to lit.
• The glowing light is evidence that energy is transferred.
• Energy transfers through electricity from power plants to homes, schools, and businesses via power lines, which can heat toasters or light rooms.