Lesson 1
What is the formula for Kinetic Energy?
Kinetic Energy = 1/2 x m x v2 the v in this equation is the same thing as speed, and the m in this equation is mass.
What is chemical energy, nuclear energy, and electrical energy?
Chemical energy is the energy that is stored in the atoms and molecules in compounds. It becomes kinetic energy when you take out atoms or molecules completely apart. Nuclear energy is the energy that comes from the relative position that is inside the nucleus of atoms. Electric energy is kinetic energy when power is being used, and is potential when no power is being used.
Identify the characteristic that makes a substance a good thermal conductor.
Good thermal conductors are often denser materials, and their molecules and atoms are really close together.
What is the difference between kinetic and potential energy?
Kinetic energy is the object at motion, and potential energy is when an object has the potential to move but is not moving. Example: An apple connected to the tree has potential energy,when the apple falls it has kinetic energy. A ball at the top of the hill has potential energy, but when it rolls down the hill it has kinetic energy.
Why is kinetic energy more efficient for doing work than thermal energy?
Kinetic energy is more efficient for doing work because thermal energy is much more diffuse than kinetic energy which makes thermal energy not do much work.
Name kitchen materials that should have high thermal conductivity.
Kitchen materials that should have high thermal conductivity are really all the materials that are made out of stone or steel.
What is the formula for Gravitational Potential Energy?
Gravitational Potential Energy = m x g x h, where m always equals 9.8 m/s2.
Give two-three real life examples of energy transformations.
A roller coaster would be an example of energy transformation. On the top of the hill the roller coaster has potential energy, and while it’s going down it has kinetic energy. Another one would be the conversion of chemical energy in car engines and the conversion of light energy in leaves.
Identify the states of matter and the processes of change.
The states of matter are Solid, Liquid, and gas. The processes that they change go melting, evaporation, and sublimation, or deposition, condensation, and freezing.
What two variables affect gravitational potential energy?
The two factors that affect gravitational potential energy is the mass and position relative to Earth.
If your body is defined as a system, in what ways is energy transferred between it and its surroundings?
Heat energy is transferred from your body to your surroundings when you sweat or are outside on a cold day. Mechanical energy is transferred when walking, running, or pedaling a bike. All work is a transfer of body energy from potential to kinetic energy.
Compare and contrast the transfer of thermal energy by conduction, convection, and radiation
Conduction is when thermal energy is transferred through a substance without a substance moving as a whole. An example of conduction would be a soon heating when placed in hot water. Radiation is the transfer of thermal energy by electromagnetic waves. An example would be sunlight warming the Earth. Convection is when thermal energy is by the motion of a hot substance from a hot region to a cold region. An example would be boiling water moving in a pan.
What are the energy forms and energy composition?
Mechanical energy is kinetic and potential, light is kinetic, sound is kinetic and potential, chemical energy is potential, nuclear energy is potential, elastic energy is potential, thermal energy is kinetic and potential, and electric energy is kinetic when power is being used, and potential when no power is being used.
How does the Celsius scale differ from the Kelvin scale?
The Kelvin scale has no degrees mark, the kelvin scale has no negatives, the kelvin scale starts its zero at the absolute zero point which is the coldest it can possibly be, and celsius starts its zero when it is at the freezing point.
Describe ways in which thermal energy is used.
Thermal energy is used for cooking and heating our homes. It is also used in heat engines, which include car engines, jet engines, and the steam turbines often used to generate energy.