Unit 3, Lesson 2: Energy Transfer
Temperature
A measure of the avergae kinetic energy of particles.
Which planet would you expect to have the thickest atmosphere?
A planet with a cold atmosphere and a strong gravity
Where does radiation occur on Earth?
Almost all of the energy on Earth is transmitted from the sun by radiation. When solar radiation reaches the Earth, some of the energy is scattered by Earth's atmosphere. But much of the energy passes through Earth's atmosphere and reaches Earth's surface. Some of the energy that Earth recieves from the sun is absorbed by the atmosphere, geosphere, and hydroshpere. Then, the energy is changed into thermal energy. This thermal energy may be reradiated into the Earth system or into space.
Where does convection occur on Earth?
Convection can occur in the air around us, waters like oceans, and deep under Earth's surface like in the mantle.
Where does conduction occur on Earth?
Energy can be tranfered between the geosphere and the atmosphere by conduction. Conduction can happen between the particles of air and the warm ground within only a few centimeters of Earth's surface. Conduction can also happen between the particles of air and the particles of water. There is a very slow process of conduction inside Earth, between the rock particles. Since rock is a poor conductor of heat this happens slowly.
Radiation
Is the transfer of energy as electromagnetic waves.
Conduction
Is the transfer of energy from one object to another object through direct contact. Conduction involves the faster-moving particles of the warmer object transferring energy to the slower-moving particles in the cooler object. The greater the difference in energy of the particles, the faster the transfer of energy by conduction occurs.
Specific heat
The different rates at which materials become warmer or cooler are due to a property called specific heat. A substance that has a high specific heat requires a lot of energy to show an increase in temperature. A subsatance with a lower specific heat requires less wnergy to show the same increase in temperature.
Heat
The energy transferred between objects that are at different temperatures.
Thermal expansion
The increase in volume that results from an increase in temperature.
Thermal energy
The total kinetic energy of particles.
Convection
The transfer of energy due to the movement of matter.
Convection currents
These currents form where cooler matter sinks and pushes warmer less dense matter upward.
What are three of Earth's spheres in which energy is transferred by convection?
Three of Earth's spheres in which energy is transferred by convection are the atmosphere, geosphere, and hydrosphere.
What is the direction of energy transfer between objects that are at different temperatures?
When objects that have different temperatures come into contact, enrgy will be transferred between them until both obejcts reach the same temperature. The direction of this energy transfer is always from the object with the higher temperature to the object with the lower temperature.
