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. Kira wants a pan bottom that heats food fast. Using the table, which material is best?

    • Wood, since it keeps heat in
    • Air
    • Copper
    • Steel, since metal stays colder
  6. A heater sits on the floor of Milo's classroom, but the air near the ceiling is warmest. Why?

    • Radiation skips the floor
    • Warm air rises and cooler air sinks
    • The ceiling makes its own heat
    • Cold air flows down out of the ceiling
  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?

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

    • Radiation pushes the air
    • The sand gives off wind
    • The sea pushes cold onto the land
    • 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 radiation
    • By conduction through space
    • By convection currents in space
    • 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?

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

    • It conducts warmth from the air
    • It keeps the cold out
    • It makes its own heat
    • It absorbs more radiation
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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. Kira wants a pan bottom that heats food fast. Using the table, which material is best?

    • Wood, since it keeps heat in
    • Air
    • Copper
    • Steel, since metal stays colder
  6. A heater sits on the floor of Milo's classroom, but the air near the ceiling is warmest. Why?

    • Radiation skips the floor
    • Warm air rises and cooler air sinks
    • The ceiling makes its own heat
    • Cold air flows down out of the ceiling
  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?

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

    • Radiation pushes the air
    • The sand gives off wind
    • The sea pushes cold onto the land
    • 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 radiation
    • By conduction through space
    • By convection currents in space
    • 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?

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

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