A brass ball is too large to pass through a brass ring.

Use heat and temperature to design a strategy to allow the brass ball to pass through the ring.

You must use 2 strategies to complete this task.

Heat the ring (expansion) or dip the ball in super cold dry ice solution (contraction)

As the temperature reading on a thermometer goes from 2°C to 48°C, what is happening to the particles?

Use the particle theory to explain your answers.

Kinetic energy of the water molecules increases. This causes the particles to move quicker as well as further apart (expansion) and thus stretch upwards inside the thermometer.

Draw a picture of the telephone lines in the summer vs the winter.

In the summer, the cables will expand and get longer like a stretched out elastic band. They will hang low. In the winter they will shorten and contract thereby tightening up.

The tires on a car are filled with compressed air. In the winter, when the air temperature drops very low, the tires become slightly flat, even when they are not leaking because

The spaces between the air particles decrease and cause the volume to decrease. Low temperatures cause air particles to contract thereby reducing their volume. This is the correct answer.a.

b. The spaces between the air particles decrease and cause the volume to increase.

c. The spaces between the air particles increase and cause the volume to decrease.

Describe 2 things that happen to the particles that make up ice cream when you:

A) Remove heat from them.REMOVING heat from particles causes them to move slower and bunch up closer and tighter together. The ice cream would turn harder and more icy if you REMOVE more heat from it. You could do this by placing the ice cream inside of a deep freezer.

B) Allow them to absorb heat.When particles ABSORB heat, they move faster and start to separate from one another. This would cause the ice cream to soften up and liquefy. Some people call it melting. You can do this by placing your ice cream outside on a hot day. The ice cream will ABSORB the heat from the air.

Then provide an example of a real life situation that could cause A and B to happen.

Jimmy had 2 ice cubes that were the same size. He put each one on top of a wooden table. The first one was exposed to air. The second one was wrapped in a fuzzy cotton blanket.

Which ice cube will melt first? Explain your answer.

The ice cube left out in the open will melt first because heat from the air (hot/warm) will move into the ice cube (cold) because heat moves from hot areas to colder areas. The ice cube that is wrapped up inside of the blanket will be protected by the blanket’s insulating properties. The blanket will slow the passing of heat from the air into the ice. In other words, the blanket acts as a shield to slow down the flow of heat towards the ice. If the ice cube doesn’t absorb as much heat, then it does not melt as quick either.

Name the phase change that occurs when:

A) Dry ice disappearsSublimation

B) water vapor becomes frost on a car windshieldSublimation (sublimation is solid to gas as well as gas to solid)

C) water boils in a pot on the stove.Evaporation

D) Water vapor becomes liquid droplets in a cloud.Condensation

E) Ice cream runs down your hand.Melting…also known as fusion.

F) A puddle turns into ice.Freezing…aka…solidification.

Use the principle of convection to explain why your shower curtain gets pulled in towards you when you shower with hot steamy water.

The shower curtain acts as a barrier. The air inside the shower curtain is much hotter so it rises. Remember that when hot air rises, it creates a bit of a suction vacuum on each side sucking cold air in towards the action.

This suction force pulls colder air outside of the curtain in towards you. It’s the same reason forest fires create suction in towards the fire.

Why does hot coffee burn you the moment you spill it on yourself?Hot coffee is hot because the molecules have high kinetic energy/heat. Heat always moves from high temp areas to low temperature areas. It just so happens that your skin is lower in temperature. Therefore the coffee’s energy passes into your body very quickly causing your cells to overheat and burn….we know it as “OUCH!”

Why does that same coffee feel cold on your skin 10 seconds later?

After a few seconds, the hot water molecules that make up the coffee evaporate by jumping into the sky. The slower water particles remain and they are really hungry for heat so they steal it from your body…we call that “Oooh Cooold!”

Explain how conduction transfers heat. (Include diagram)Conduction transfers heat through collisions…think dominoes. One molecule gets excited and it passes on the vibrations to the next and then to the next until it spreads across the entire surface of the conductor.

What states of matter does conduction occur in? Conduction is most effective in solids.

Explain how convection transfers heat.(Include diagram)Hot gas/liquid heats up and rises. Then it cools and falls back down to be reheated again. This creates a convection current.

What states of matter does convection occur in? Convection occurs only in fluids (Liquids/Gases)

Which 3letters represent a change of state that “ABSORBS” energy? How do you know?

ABSORBING ENERGY causes an increase in kinetic energy. Only A, C, and E show a phase change where the molecules get more energetic. For example, molecules in a solid are rigid and slow, but in a liquid they move faster…..it must have absorbed energy to make that happen.

F

Identify……The temperature that Silver becomes a liquid: 962 C

The temperature at which Silver becomes a solid:962C (Recall that melting and freezing temperatures are the exact same value)

The temperature at which Iron melts: 1535 C

The temperature at which iron condenses: 1535 C Recall that condensation and boiling occur at the same temperature.

Identify the state of matter of….

Table salt at 900oC: Liquid

Lead at 327oC: Solid

Water at 98oC: Liquid

Gold at 29000C: Gas

Draw a diagram explaining how a water heater tank works. (Standard ones found in your basement)

You must include the source of heat in your explanation.

A hot water tank usually burns gas (the blue flame at the base). The heat transfers up a solid metal pipe that goes up the center. This is called conduction. From there, the heat spreads sideways into the cold water that has filled up the tank.

Draw a diagram of how a thermostat turns your furnace on and off.

When you move the dial to the right, the mercury inside of the bulb rolls down and touches the gap in the wire. This connects the circuit (mercury conducts electricity because it is a metal…just in liquid form) and starts up the furnace.

As the room heats up, the bimetallic coil that holds up the mercury tube, starts to unwind because it is sensitive to temperature. As it unwinds, the mercury bulb starts to tilt in the opposite direction until the mercury disconnects from the wires and breaks the circuit. The furnace stops.

What is the purpose of building bridges with gaps in between?

Is it likely that this picture was taken in the summer or in the winter?

Bridges have spaces in between the chunks of bridge to provide space for the metal and concrete to grow into during the summer season. Judging from the

amount of space in between the segments of bridge, this pictures was likely taken in the winter. The metal looks short and has lots of room to grow into once the

hot season arrives.

Explain how the liquid in a thermometer goes up and down depending on the temperature?

The liquid in the thermometer expands and stretches out when the temperature in the room increases and contracts(shortens) when the temperature of the room decreases.

2. In which of the following does convection NOT occur?a. Oil

b. Waterc. Copper

d. Air

Copper. Copper is a solid. Convection does not occur in solids. Convection only occurs in liquids and gases (Fluids)

When Jamile goes running he sweats a lot. An hour after he runs his sweat is gone.

What happened to the sweat? Why?

The sweat evaporated. This means that the sweat must have absorbed heat from Jamile’s body and used it to

launch itself into the air thereby “disappearing” into thin air.

Why are windows made using a thin layer of air sandwiched in between two sheets of glass?

What is the importance of the air in this design?

What would happen if the window was made of only 1 sheet of glass?

Glass is a great conductor of heat. Air is a great insulator of heat (many people forget this…Air is a gas and gases do not conduct heat very well). This is especially important if your goal is to prevent heat from escaping out your windows. Triple pane glass (3 glass layers) would have an extra layer of air making the window even better at trapping heat inside of a building….it’s more expensive to buy too.)

If the window was only made of 1 layer of glass and no air, then the glass would conduct most of the heat inside of a building to the outside world. This means your furnace would have to work even harder at keeping your home or office warm. That would be a huge waste of energy.