Energy Study Guide Review

What factors affect the GPE an object has and how? Mass and height; the more mass and the higher from the earth’s surface, the more GPE

Green plants convert light energy from the sun into ___________energy. Chemical potential

State the law of conservation of energy. Energy cannot be created or destroyed. It can change form.

What unit is used to measure thermal energy? kinetic energy? GPE? Joules is the unit for all forms of energy

Kinetic energy depends on what two factors? Mass and velocity

Name some devices that use electrical energy. A computer, toaster, an electric guitar, light bulb, etc.

A bus engine transfers _______ energy into ____ so that the bus moves. Chemical potential (gas) into kinetic (moving bus)

According to the law of conservation of energy, the total amount of energy in the universe ____. Remains constant

What is the SI unit for energy? Joules

Mechanical energy is the sum of what types of energy Mechanical energy is the sum of what types of energy? Give an example of an object’s mechanical energy. You may illustrate and label or explain. the total amount of potential and kinetic energy in a system; a child on a swing or a ball being thrown

If an apple falls from a tree what can be said about the potential energy, kinetic energy, and its mechanical energy in relation to each other? Mechanical energy will remain constant; there is a conversion from initial GPE to KE as the apple falls, then KE to PE as the apple lands.

What is nuclear fusion? Where does it occur? a small amount of mass is transformed into a tremendous amount of energy when the nuclei of atoms combine; the sun and stars

When you move your hand what type of energy change occurs? Chemical potential to kinetic

When you rub two sticks together this type of energy change occurs? Why? Kinetic energy to thermal energy; friction

What unit is used to tell us how much energy we get from foods? Calories

Define energy. the ability to cause change

A hammer falls off a roof top and strikes the ground with a certain kinetic energy. If it fell from a roof twice as tall, how would its kinetic energy compare? How would its potential energy be different on the higher versus the lower roof before it fell?   As it had twice as much GPE, it will also have twice as much KE; more potential on the higher roof

Which components of food contain calories Which components of food contain calories? Which contain the most calories? Carbohydrates, proteins, and fats; fats contain 9 Calories per gram as opposed to 4 Calories in proteins and carbs

Identify a situation where it is possible for a ball to have both kinetic energy and potential energy at the same time? Explain. A bouncing ball’s ME is continually fluctuating between KE and GPE

A ball has 100 J of potential energy when it is on a shelf A ball has 100 J of potential energy when it is on a shelf. Explain what happens to the potential energy and the kinetic energy as the ball falls. Explain what happens to ME. GPE decreases as it converts to increasing KE ME remains constant

A dump truck, a sports car, and a bicycle are traveling at the same velocity. Compare their kinetic energies. The dump truck has the most mass, so the most KE because velocity is not a factor. The bicycle would have the least KE for the same reason.

What electric conversions occur in a toaster? Electrical energy to thermal energy and light

Which position of the rolling ball has the most potential energy Which position of the rolling ball has the most potential energy? Most kinetic? A has the highest PE because of height; D would have the highest KE

When you are on a swing and pumping your legs you continue moving When you are on a swing and pumping your legs you continue moving. When you stop pumping your legs, you will eventually stop. Explain why. Does this violate the law of conservation of energy? Explain. Kinetic energy is converted to thermal energy due to air resistance and friction between the swing’s ropes or chains where they connect; it does not violate the Law because energy is not destroyed, it simply changes form

Where does the energy that moves through earth’s ecosystems come from? the sun

Why is sunlight important to life on earth? Source of energy that powers food chains and webs

What is thermal energy? the sum of the kinetic and potential energy of all the particles in an object.

How are thermal energy and kinetic energy related? Kinetic energy is easily converted to thermal energy because of friction; also, as thermal energy increases, the kinetic energy of particles increase as well

The Sun is our local star. Where does the sun’s energy come from The Sun is our local star. Where does the sun’s energy come from? What type of energy does the sun send to Earth? Fusion reactions between hydrogen atom nuclei forming helium and releasing radiant energy

Describe what chemical energy is Describe what chemical energy is. What does chemical energy have to do with the process of photosynthesis? One product of photosynthesis is glucose, which stores large amounts of chemical potential energy

What are the starting and ending materials in the process of photosynthesis? Starting Materials Converted to Ending Materials    carbon dioxide water sunlight  glucose oxygen

How do cells that make up living things release energy? Cellular respiration releases stored energy from food that is consumed (animals) or produced (plants)

The sun provides energy to producers and the energy flows through the ecosystem in food chains and food webs. Describe both. Food chain- energy flows from producers to various levels of consumers Food web- links various food chains in an ecosystem