Energy changes form

Answer Key - Grade 8 Science Worksheet

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

1. 1.

   Ari's coaster chart shows a point partway along the ride. Using the bar chart, how much energy is thermal there?

   100 J
2. 2.

   Bo coasts to the bottom of a long hill. Using the bar chart, how much energy is thermal at the bottom?

   150 J
3. 3.

   Esme's sled is partway down a bumpy slope. Using the bar chart, how much energy is thermal there?

   80 J
5. 4.

   On the same track, at which point is the cart's stored energy smallest, Kira?

   • At A, where it barely moves
   • At B
   • Stored energy is zero everywhere
   • At C
6. 5.

   Between B (5 m) and C (18 m), the cart climbs. Which energy change happens, Luz?

   Use the picture in question 4.

   • Stored → motion
   • Motion → stored
   • Motion → nothing
   • Thermal → stored
7. 6.

   Milo pedals a bike up a hill, using energy from breakfast. Which energy change mostly happens on the way up?

   • Thermal energy → chemical energy
   • Motion energy → nothing
   • Chemical energy → stored energy
   • Stored energy → chemical energy
8. 7.

   Noah coasts down the other side without pedaling and speeds up. Which energy change happens?

   • Chemical → stored
   • Motion is used up
   • Stored → motion
   • Motion → stored
9. 8.

   At the bottom, Pia brakes to a stop and the rims feel warm. Which energy change happens?

   • Motion → thermal
   • Stored → chemical
   • Motion → nothing
   • Thermal → motion
10. 9.

    Ren drops a play ball, and each bounce is lower than the last. Where did the missing energy go?

    • Into stored energy that stays in the floor
    • Into thermal energy and sound
    • Into making the ball lighter
    • It was used up by bouncing
11. 10.

    Zee's toy car rolls across a carpet and slowly stops. Where did its motion energy go?

    • Back into the batteries
    • The carpet destroyed it
    • Into stored energy in the car
    • Into thermal energy in the car and carpet