8th grade Conduction, convection and radiation worksheet

Conduction, convection and radiation

Grade 8 Science Worksheet

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

1. 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. 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. 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)

   material	conductivity (W/(m·K))
   copper	400
   steel	50
   glass	1
   wood	0.15
   air	0.026

5. 4.

   Jun picks a material for a pot handle that should stay cool. Use the table. Which is best?

   • Copper, since metal feels cool
   • Wood
   • Steel, since it is strong
   • Glass, since you can see through it
6. 5.

   Double windows have a layer of air between two sheets of glass. Using the table, why does that help, Luz?

   • Air conducts heat poorly
   • Glass conducts better than steel
   • The air layer makes warmth
   • Air keeps out the cold
7. 6.

   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
   • Convection
   • Conduction
8. 7.

   On a sunny afternoon at the beach, a breeze blows from the sea toward the land. Why, Pia?

   • Radiation pushes the air
   • The sea pushes cold onto the land
   • The sand gives off wind
   • Warm air over the land rises, and sea air moves in
9. 8.

   Ren learns that space between the Sun and Earth is almost empty. How does the Sun's energy reach Earth?

   • By radiation
   • By convection currents in space
   • By conduction through space
   • It can't cross empty space
10. 9.

    Tala's family car is parked in the sun with the windows shut. The dark seat gets hot. How did the energy arrive?

    • Radiation from the Sun
    • Conduction from the warm air outside
    • Cold leaving the seat
    • Convection from the engine
11. 10.

    Zee lays a black shirt and a white shirt in the sun. Why does the black one warm faster?

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