Electrostatics and Thermodynamics AP 2

Convection is a form of heat transfer in fluids (liquids and gases) which requires movement of the fluid particles. Typically, hot fluid in contact with a surface at higher temperature rises and colder fluid moves down to take its place, setting up convection currents and moving heat from one region of a fluid to another.

Conduction results in a transfer of energy (mainly in solids) by collision of more energetic molecules with less energetic ones. Radiation results in energy being transferred via electromagnetic waves. Match the following phenomena with the correct mode of heat transfer.

• Convection

• 
• Radiation

• The other end of a metal skewer holding a marshmallow in fire gets hot

• Conduction

• 
• Convection

• The air above a fire is hotter than the air on the side

• Conduction

• Seaside is often breezy because of different temperatures of the land and water

Tags

NGSS.HS-PS3-4

The diagram shown is the Maxwell Boltzman distribution of speeds of a sample of gas at three different temperatures. Rank the three graphs A, B & C from the lowest temperature to the highest temperature.

• A

• B

• C

Tags

NGSS.HS-PS1-5

1. An ideal gas is made up of N diatomic molecules, each of mass M. All of the following statements about this gas are true EXCEPT:

• The temperature of the gas is proportional 

         to the average translational kinetic energy 

         of the molecules.

• All of the molecules have the same speed.

• The molecules make elastic collisions with 

        each other.

• The average number of collisions per unit time that the molecules make with the walls of the container depends on the temperature of the gas.

• The molecules make elastic collisions with 

        the walls of the container.

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-2

NGSS.HS-PS3-4

When a room-temperature spoon is placed in a cold bowl of ice cream, some of the ice cream quickly melts where it comes into contact with the spoon. Which of the following is the best explanation for why the ice cream melts?

• The temperature of the ice cream is transferred to the spoon, because the temperature of the ice cream must increase if it melts.

• 1. Energy in the form of radiation will be emitted by the spoon and absorbed by the ice cream, because the ice cream must absorb energy to melt.

• The ice cream has more mass than the spoon, so    it will always absorb energy from the spoon.

• Energy is transferred to the ice cream molecules and increases their average speed, because the higher-energy molecules in the spoon are vibrating and colliding with the lower-energy molecules of the ice cream.

Tags

NGSS.HS-PS3-4

Identical rods (same dimensions) are made out of these five materials. The two ends of all the rods are kept at the same temperature difference. Rank the rods by their ability to transfer heat from the least (1) to the most(5)

• Lead

• Iron

• Aluminum

• Gold

• Copper

Tags

NGSS.HS-PS3-4

The table lists experimental data related to the conduction of energy by three slabs of metal. The slabs have identical dimensions but are made of different metals. Which of the following correctly ranks the metals’ thermal conductivities k from least (1) to most (3)?

• 3

• 2

• 1

Tags

NGSS.HS-PS3-4

In a region of space, there is an electric potential field with isolines as shown in the figure. Which of the following is the most accurate description of the electric field in the region?

• An electric field is directed to the left with a uniform strength

• An electric field is directed to the right with a uniform strength

• An electric field is directed to the left that increases in strength from left to right

• An electric field is directed to the right that increases in strength from right to left

Isolines of equal electric potential in a region of space are shown in the figure. Points A and B are in the plane of the isolines. Which of the following correctly describes the relationship between the magnitudes and directions of the electric fields at points A and B?

• The E field at A and B have the same magnitude and direction

• The E field at A and B have the same magnitude but opposite directions

• The E field at A and B have the same direction but different magnitudes

• The E field at A and B have different magnitudes and directions

Tags

NGSS.HS-PS2-4

NGSS.HS-PS3-5

• The electric potential at P can be zero

• The electric field at P can be zero

• The Electric Field at P changes direction depending on whether a + or a - test charge is placed there

• The Electric Field at P depends only on the charges shown, regardless of what charge we may place there

Tags

NGSS.HS-PS2-4

Calculate x if the electric potential at P = 0

• 0.5 m

• 5 m

• 2 m

• 2.5 m

Tags

NGSS.HS-PS3-5