What is Energy?
True or False: All moving objects have kinetic energy.
True
This form of energy results from vibrations in the particles in the air, allowing you to hear noises.
Sound energy
What kind of energy is due to the kinetic energy of all the moving particles in a substance?
Thermal energy.
These machines convert the chemical energy from fossil fuels into electrical energy, what are they called?
Electrical generators
What is the ability to do work?
Energy
This form of energy is the energy of moving electrons.
Electric energy.
What force opposes motion between two surfaces that are touching and sliding against each other?
Friction
This source of energy is found as a result of heating of the Earth's crust.
Geothermal energy
What is happening to an object if the potential energy is decreasing?
Kinetic energy is increasing.
This form of energy is always given off due to friction.
Thermal energy.
Which law states that all energy is moving from hot to cold, and from highly concentrated to spread out?
The Law of Entropy (the Second Law of Thermodynamics)
This type of resource cannot be replaced or is replaced much slower than it is being used. What is it?
Nonrenewable resource
The Law of the Conservation of Energy states...
Energy cannot be created or destroyed, only transferred or converted to another form.
If kinetic energy increases, what happens to the thermal energy? Does it increase or decrease?
It increases.
Explain the energy conversion involved in a hairdryer.
Electric energy goes in and is converted to thermal energy, sound, and kinetic (or mechanical) energy.
After all energy conversions are done, how much energy do you end up with in a system compared to the original amount of energy in the system?
The same amount of energy (because energy cannot be created or destroyed).
Nuclear power plants use this type of reaction to generate energy.
Nuclear fission
In order to calculate the gravitational potential energy of an object, what do you need to know?
The object's height and weight OR its mass, the value for g, and its height
Explain nuclear fusion and how it relates to our sun.
Nuclear fusion is the reaction in which two or more nuclei fuse together, giving off energy. Our sun gets its energy from this source. Hydrogen nuclei fuse together to make a larger Helium nucleus. This is where we get our sun's light and heat.
Name and describe the process whereby plants make and store chemical energy.
Photosynthesis. It is the process where plants take energy from the sun and convert carbon dioxide and water to make glucose and oxygen.
On the first hill of a roller coaster, is the kinetic energy at its greatest, least, or will it always be the same?
Least
Calculate the height of a bowling ball if it weighs 70N and it has a gravitational potential energy of 350J.
GPE = weight(w) x height(h) So...
height = GPE / weight
h=350J / 70N
h=5m