Speed and energy · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Speed and energy

Science · Energy · ages 9-10
Name ______________________   Date ____________

  1. Knowing that a light ball is faster than a heavy ball is enough to decide which has more kinetic energy.

    Circle one:   True   False

  2. Nia wants to test how speed affects kinetic energy. Which plan keeps the object's mass the same?

    • Use one car at two different speeds
    • Use a light car, then a heavy truck
    • Use two cars with different masses
    • Use a small ball, then a large rock

  3. What do we call the energy a moving object has?

    • Kinetic energy
    • Stored energy
    • Light energy

  4. A ball that is sitting still has kinetic energy.

    Circle one:   True   False

  5. A fast car hits a block on carpet. A slower identical car hits the same block on a smooth floor. The carpet trial moves the block less. Why is this not a fair comparison of collision effects?

    • The same block must have the same travel distance
    • The faster car cannot have any kinetic energy
    • Different surfaces can change the block's travel

  6. Identical toy trucks hit identical soft panels in the same way. In repeated trials, Truck A makes a small dent and Truck B a larger dent. Which results suggest more kinetic energy at impact?

    • Truck A's trials
    • Truck B's trials
    • Both sets equally

  7. In repeated trials, balls with the same mass hit identical skittle setups in the same way. The chart shows typical results. Which ball's results suggest greater speed at impact?

    A: 1skittle1B: 6skittles6
    • Ball A
    • Both equally
    • Ball B

  8. The same car hits the same block on one surface. Slow trials move it 2, 3 and 2 cm. Fast trials move it 7, 8 and 7 cm. What do these results support?

    • The slower car carried more kinetic energy
    • The faster car carried more kinetic energy
    • Changing speed had no effect on kinetic energy

  9. Amir says, 'The same ball has more kinetic energy when it rolls slowly because it takes longer to stop.' Which sentence corrects his reasoning?

    • A longer stopping time always means more kinetic energy
    • The same ball has equal kinetic energy at every speed
    • Compare its speed; the faster roll has more kinetic energy

  10. In matched trials, a block moves 5 cm after a slow-car collision and 12 cm after a fast-car collision. How many centimetres farther does it move in the fast trial?

    Answer: ______________

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Speed and energy W1-mt_2Um22lTBZV-s1

  1. False · Both mass and speed matter. The same-mass speed rule cannot settle this comparison.
  2. Use one car at two different speeds · Using one car changes speed without changing the object's mass.
  3. Kinetic energy · Kinetic energy is another name for the energy of motion.
  4. False · Kinetic energy comes from motion. A still ball has none of it.
  5. Different surfaces can change the block's travel · Carpet can stop the block sooner. Changing surface as well as speed prevents a matched comparison of the effects.
  6. Truck B's trials · Under matched conditions, Truck B's larger dents suggest it transferred more energy at impact.
  7. Ball B · With mass and collision conditions matched, Ball B's greater effect suggests more kinetic energy and greater speed at impact.
  8. The faster car carried more kinetic energy · Every fast trial moves the block farther than every slow trial. The repeated pattern supports greater kinetic energy at greater speed.
  9. Compare its speed; the faster roll has more kinetic energy · For the same ball, greater speed means more kinetic energy. Stopping time alone does not establish its energy.
  10. 7 · Compare the distances by subtraction: 12 minus 5 = 7 cm.
Worksheet · LightMySky