Types of Energy
energy from an object being stretched or deformed.
elastic potential
When an object produces light, what other type of energy is often produced?
thermal
Explain why an object with a smaller mass travelling at a much higher velocity would have more kinetic energy than an object with a greater mass travelling at a much slower velocity.
The formula for KE = 1/2m X v squared.
What is a line graph used to show?
relationships between 2 variables.
What type of heat transfer is occurring as you bake brownies in an oven?
radiation and convection
Energy of motion
kinetic
When you stick your hand into "cold" water, why does your hand feel cold? How is energy transferring?
Always from warmer (your hand) to colder (cold water). You feel cold because your energy is being transferred.
What type of potential energy occurs when you pull back a rubber band? How does that energy transform as you release the rubber band?
elastic potential energy. PE is greatest when pulled back and KE is minimal. KE increases and PE decreases as you release.
What variable always goes on the x-axis?
What type of energy transformation does NOT require a medium? Give an example.
radiation - sun traveling through empty space
energy stored in our food and in bodies
chemical potential
What type of energy transformation occurs when you turn on the lights in the classroom?
mechanical to electrical to radiant to possible thermal and possible sound
Kayla loves roller coasters. She rides from the top of hill x to the top of hill y before the ride gets stuck. What type of energy transformations occurred from Hill x to Hill y?
potential to kinetic to potential.
Draw a graph that shows the relationship between height and potential energy.
linear graph
Explain how the the side of a rock NOT facing the sun can increase in temperature throughout the day.
conduction - as molecules get heated, they transfer energy in the molecules they are in contact with.
Energy of moving electrons
electrical
What type of energy transformation occurs with a car engine?
Chemical to mechanical
As a pendulum swings, how does the percentage of PE, KE, and ME change as it falls?
PE is greatest at the top and decreases at it falls. KE is 0 at the top and increases as it falls. ME remains the same (total energy) IF there is no friction. With friction, some is transferred to thermal energy so ME would decrease slightly.
Draw a graph that shows the relationship between mass and energy
linear graph
Explain how convection works when you boil water in a pot on the stove.
water near the heat source becomes less dense as water molecules speed up and spread out. This rises. Water near the air cools off slightly causing the molecules to contract and sink.
Mechanical
Ava is riding her bicycle across a gravel road. She STOPS pedaling and eventually the bicycle comes to a stop. Explain the type of energy transfer occurring.
mechanical to thermal
Draw a graph that shows the relationship between velocity and energy. Explain what it shows.
top-opening parabola; as velocity increase, energy increases at a faster rate.
Eli designs an experiment to show convection. He heats up water and puts it in one bottle. He places ice water in a different bottle. He pours the cold water into the bottle with warm water. What will occur that shows convection?
The colder, more dense water will sink.