Heat Transfer Scenes
1. Steaming Hot Chocolate
The hot chocolate is at a higher temperature than the surrounding air and mug. Heat is transferred from the hot chocolate to the mug and cooler air above the hot chocolate. We see “steam” (tiny water droplets suspended in air) above the top of the mug because the hot chocolate warms the moisture filled air above the mug and causes the water in the air to condense into tiny droplets that we can see as “steam.”
2. Hot soup with metal spoon
The hot soup is at a higher temperature than the metal spoon. Heat is transferred from the soup to the metal spoon through direct contact.
3. Boiling water
The pot becomes hot from touching the heat element. In turn, heat is transferred from the pot to the water that is touching the sides of the pot. As the water heats, hot water rises and cold water sinks. As that water gets hotter, it rises. And the cycle continues.
4. Woodstove
Heat from a woodstove is transferred in two ways. The fire heats the woodstove. The woodstove becomes hot. The air touching the woodstove is heated. As the air warms, it rises. The cooler air sinks. Heat waves from the metal on the stove also help warm the room.
5. Mirage
Heat from the Sun warms the black asphalt. The air molecules directly above the asphalt are become much hotter than the surrounding cooler air. A wavy and often duplicate image appears because light bends when it passes from one medium to another; in this case, from warmer air to cooler air.
6. Woman Peeking in Oven
In the oven, hot air rises and cold air sinks. The cold air heats up, it rises and the cycle counties. Heat is transferred to items placed in an oven throughthis cycle. Heat is also emitted from the hot walls of the oven.
7. Ice cream melting in Sun
Heat from the Sun is transferred to the lower heat ice cream, causing the ice cream to melt. The heat waves warm up the ice cream.
8. Heat lamp
The heat from the lamp warms the air molecules, similar to the melting ice cream example.
Heat Transfer Scenes
1. Steaming hot chocolate
a. Conductionc. Radiation
b. Convection
2. Hot soup with metal spoon
a. Conductionc. Radiation
b. Convection
3. Boiling Water (Two or more answers)
a. Conductionc. Radiation
b. Convection
4. Woodstove (Two or more answers)
a. Conductionc. Radiation
b. Convection
5. Mirage (Two or more answers)
a. Conductionc. Radiation
b. Convection
6. Woman peeking in oven (Two or more answers)
a. Conductionc. Radiation
b. Convection
7. Ice cream melting in the Sun.
a. Conductionc. Radiation
b. Convection
8. Heat lamps
a. Conductionc. Radiation
b. Convection
Heat Transfer Sciences – Key
1. Steaming Hot Chocolate – B. Convection
2. Hot soup with metal spoon – A. Conduction
3. Boiling water – A. Conduction, B. Convection
4. Woodstove – A. Conduction, B. Convection, C. Radiation.
5. Mirage – B. Convection, C. Radiation
6. Woman Peeking in Oven – B. Convection, C. Radiation
7. Ice cream melting in the Sun – C. Radiation
8. Heat Lamps – C. Radiation
Heat Transfer Scenes – Scoring Guide
1. B (3 choices)2. A (3 choices)
3. A, B (3 choices)
4. A, B, C (3 choices)
5. B, C (3 choices)
6. B, C (3 choices)
7. C (3 choices)
8. C (3 choices) / Scoring Guide
8 – 4
6-7 – 3.5
5 – 3
4 – 2
3 – 1
1-2 – .5
0 – 0