Energy & Motion

Which transformation of energy occurs when a fan is turned on and the blades start to rotate?

• thermal energy to kinetic energy

• electrical energy to kinetic energy

• thermal energy to potential energy

• electrical energy to potential energy

The drawing shows a blender, which uses spinning blades to chop up fruits and other foods. What causes the blades to spin?

• Electrical energy flows through the wire and into the blender, where the energy turns into mechanical energy that spins the blades.

• Light energy enters the blender through the clear glass, where the energy turns into motion energy that spins the blades.

• Mechanical energy from pushing the buttons on the blender turns into heat energy that spins the blades.

Tags

NGSS.MS-PS3-5

When a person bends a glow stick, a small chamber inside it breaks, releasing a substance that reacts with other substances inside the glow stick. The reaction that takes place causes the glow stick to glow. What type of energy transformation is this?

• sound energy → light energy

• chemical energy → light energy

• thermal energy → light energy

• electrical energy → light energy

A cup of hot chocolate has a spoon in it. How does the heat move from the hot chocolate to the metal spoon handle?

• It moves through conduction, because heat is transferred directly from the hot chocolate to the spoon.

• It moves through convection, because heat is transferred directly from the hot chocolate to the spoon.

• It moves through conduction, because heat is transferred through density differences.

• It moves through convection, because heat is transferred through density differences.

When thermal energy is added to an object the motion of the particles

• decreases.

• increases.

• remains unchanged.

• decreases, then increases.

Tags

NGSS.MS-PS1-4

The air molecules around a candle flame are excited by the increased energy and spread out, decreasing in density and rising above the cooler, denser air around it. The denser air fills the space of the lighter air, continuing the cycle.

• conduction

• convection

• radiation

• subduction

Tags

NGSS.MS-ESS2-6

A sunbather at the beach absorbs the thermal energy from the sun through

• conduction.

• radiation.

• convection.

• a combination of all three.

If the same amount of heat is added to 25.0 g samples of each of the metals in the chart, which metal will experience the largest temperature change?

• Ca

• Fe

• Ag

• Au

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Javier is designing a container to hold cold items. Which substance should Javier use to best insulate the container?

• air, because it requires a lot of energy for air to change temperatures

• copper, because it requires very little energy for copper to change temperatures

• glass, because it requires a lot of energy for glass to change temperatures

• iron, because it requires a very little energy for iron to change temperatures

Tags

NGSS.MS-ETS1-1

NGSS.MS-ETS1-2

NGSS.MS-PS3-4

Henrietta wants to choose a metal that has the best rate of heat conduction so she can use it to make a new frying pan. Four metals and their specific heats are given in the table.

• A. iron

• B. nickel

• C. copper

• D. aluminum

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

NGSS.MS-PS3-5