Conduction, convection and radiation

Grade 8 Science Worksheet

NameDate

Circle the best answer, or write your answer on the line.

  1. A teacher's warm water cools from 80 °C to 60 °C in 10 minutes at a steady rate. How many degrees does it drop each minute, Ari?

  2. A teacher's warm water cools from 70 °C to 52 °C in 6 minutes at a steady rate. How many degrees does it drop each minute, Bo?

  3. A teacher's warm water cools from 66 °C to 42 °C in 6 minutes at a steady rate. How many degrees does it drop each minute, Esme?

  4. Read this first

    How well materials conduct heat (thermal conductivity, rounded; Data: Engineering ToolBox) (real data, rounded)

    materialconductivity (W/(m·K))
    copper400
    steel50
    glass1
    wood0.15
    air0.026
  5. Jun picks a material for a pot handle that should stay cool. Use the table. Which is best?

    • Wood
    • Glass, since you can see through it
    • Steel, since it is strong
    • Copper, since metal feels cool
  6. Kira wants a pan bottom that heats food fast. Using the table, which material is best?

    • Steel, since metal stays colder
    • Wood, since it keeps heat in
    • Air
    • Copper
  7. A teacher warms a beaker of water on a hot plate; a drop of food coloring swirls up and around. What path is this, Noah?

    • Conduction
    • Radiation from the coloring
    • Cold water pushing up from the bottom
    • Convection
  8. On a sunny afternoon at the beach, a breeze blows from the sea toward the land. Why, Pia?

    • The sea pushes cold onto the land
    • Radiation pushes the air
    • The sand gives off wind
    • Warm air over the land rises, and sea air moves in
  9. Ren learns that space between the Sun and Earth is almost empty. How does the Sun's energy reach Earth?

    • By convection currents in space
    • By conduction through space
    • By radiation
    • It can't cross empty space
  10. Tala's family car is parked in the sun with the windows shut. The dark seat gets hot. How did the energy arrive?

    • Cold leaving the seat
    • Conduction from the warm air outside
    • Radiation from the Sun
    • Convection from the engine
  11. Zee lays a black shirt and a white shirt in the sun. Why does the black one warm faster?

    • It keeps the cold out
    • It absorbs more radiation
    • It makes its own heat
    • It conducts warmth from the air
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Conduction, convection and radiation

Answer Key - Grade 8 Science Worksheet

Circle the best answer, or write your answer on the line.

  1. A teacher's warm water cools from 80 °C to 60 °C in 10 minutes at a steady rate. How many degrees does it drop each minute, Ari?

    2 °C/min
  2. A teacher's warm water cools from 70 °C to 52 °C in 6 minutes at a steady rate. How many degrees does it drop each minute, Bo?

    3 °C/min
  3. A teacher's warm water cools from 66 °C to 42 °C in 6 minutes at a steady rate. How many degrees does it drop each minute, Esme?

    4 °C/min
  4. Read this first

    How well materials conduct heat (thermal conductivity, rounded; Data: Engineering ToolBox) (real data, rounded)

    materialconductivity (W/(m·K))
    copper400
    steel50
    glass1
    wood0.15
    air0.026
  5. Jun picks a material for a pot handle that should stay cool. Use the table. Which is best?

    • Wood
    • Glass, since you can see through it
    • Steel, since it is strong
    • Copper, since metal feels cool
  6. Kira wants a pan bottom that heats food fast. Using the table, which material is best?

    • Steel, since metal stays colder
    • Wood, since it keeps heat in
    • Air
    • Copper
  7. A teacher warms a beaker of water on a hot plate; a drop of food coloring swirls up and around. What path is this, Noah?

    • Conduction
    • Radiation from the coloring
    • Cold water pushing up from the bottom
    • Convection
  8. On a sunny afternoon at the beach, a breeze blows from the sea toward the land. Why, Pia?

    • The sea pushes cold onto the land
    • Radiation pushes the air
    • The sand gives off wind
    • Warm air over the land rises, and sea air moves in
  9. Ren learns that space between the Sun and Earth is almost empty. How does the Sun's energy reach Earth?

    • By convection currents in space
    • By conduction through space
    • By radiation
    • It can't cross empty space
  10. Tala's family car is parked in the sun with the windows shut. The dark seat gets hot. How did the energy arrive?

    • Cold leaving the seat
    • Conduction from the warm air outside
    • Radiation from the Sun
    • Convection from the engine
  11. Zee lays a black shirt and a white shirt in the sun. Why does the black one warm faster?

    • It keeps the cold out
    • It absorbs more radiation
    • It makes its own heat
    • It conducts warmth from the air