University that Wisconsin-Stevens point > CNR associated Programs > Wisconsin K-12 Energy education and learning Program > power Education: Concepts and also Practices > section B: power Transfer
​ Unit 2: Energy Rules!

Section B. Power Transfer

Energy Transfer

The 2 ways that energy can be transferred are by act work and by warm transfer.

You are watching: The transfer of energy by electromagnetic waves


Doing Work 

*
Energy have the right to be transferred from one thing to an additional by act work. To do job-related requires that an agent exert a force on an object over a distance. When occupational is done, power is transferred from the certified dealer to the object, which results in a readjust in the object's movement (more specifically, a change in the object's kinetic energy). 

An instance of how Doing occupational Transfers power from One thing to Another

Suppose the a human being (the agent) exerts a force on a wheelbarrow (the object) that is originally at rest, causing it to move over a certain distance. Recall the the occupational done ~ above the wheelbarrow through the human is same to the product of the person's pressure multiplied by the distance traveled by the wheelbarrow. Notice that once the pressure is exerted ~ above the wheelbarrow, there's a change in that is motion. That is kinetic power increases. But where go the wheelbarrow gain its kinetic energy? It come from the human exerting the force, who provided chemical energy stored in the food they ate to relocate the wheelbarrow. In other words, as soon as the human being did work on the wheelbarrow, they moved a specific amount the chemical energy to the wheelbarrow, leading to it come move. Together a result, the person's store of chemical power decreases and also the wheelbarrow's kinetic energy increases.

Heat Transfer 

Heat is the transport of energy from a warmer thing to a cooler object. For example, a lighted match (higher temperature object) will transfer warm to a huge pan filled with lukewarm water (lower temperature object). Note that the actual quantity of thermal energy each object has doesn't matter, as the pan the lukewarm water might have much more thermal energy than the match. What is necessary for heat transfer to take location is a difference in temperature between 2 objects. There is no this difference, no warm transfer can take place.

Heat can be transferred in 3 ways: by conduction, by convection, and also by radiation.

Conduction is the deliver of power from one molecule to an additional by straight contact. This deliver occurs when molecules hit against each other, comparable to a video game of pool where one moving ball strikes another, leading to the 2nd to move. Conduction takes ar in solids, liquids, and gases, however works best in products that have an easy molecules the are situated close to each other. For example, steel is a much better conductor than lumber or plastic.

Convection is the movement of warmth by a fluid such together water or air. The fluid (liquid or gas) move from one place to another, moving heat along with it. This activity of a massive of boil water or waiting is referred to as a current.

Radiation is the carry of warmth by electromagnetic waves. When you stand in the sun, you are warmed by the electromagnetic waves, mostly infrared radiation (and to a lesser extent, clearly shows light), that travels indigenous the sunlight to Earth. In addition to the sun, light bulbs, irons, and toasters additionally transfer heat via radiation. Note that, unequal conduction or convection, heat transfer through radiation does no need any matter to assist with the transfer.

See more: How Long Does It Take Wood Glue To Dry ? Wood Glue Curing Vs Drying Time

You deserve to detect evidence of warm transfer. You can see the air shimmering over a radiator (convection), placed your hand ~ above a heat spoon that's to be sitting in a hot bowl of soup (conduction), or an alert that the sunlight shine feels warm on your skin (radiation). If girlfriend need evidence of thermal energy or heat in your life, just feel her arm. Her body generates heat 24 hrs a day! (Taken from KEEP energy Education activity Guide "Exploring Heat").