Static Charge and Electric Fields · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Charge, fields, and the spark

Science · Energy · ages 14-16
Name ______________________   Date ____________

  1. Like charges repel and opposite charges attract.

    Circle one:   True   False

  2. You rub a balloon on cloth. What moves between the surfaces?

    • Electrons
    • Protons
    • Neutrons

  3. How do you draw field arrows around a lone positive charge?

    • Pointing toward it
    • Circling around it
    • Away from it

  4. Why do you get a shock touching a car door after a drive?

    • The metal door stores extra protons
    • The battery leaks current into the handle
    • Built up charge makes a fierce field across a small gap, so air conducts

  5. One sketch shows crowded field lines, another shows spread out lines. What does the crowding tell you?

    • The charge is negative
    • The field is strong there
    • The field is about to vanish

  6. Why do static tricks use a plastic comb but never a bare metal rod?

    • Metals cannot touch charge at all
    • Insulators trap shifted charge, while metals let it flow away
    • Plastic creates protons when rubbed

  7. Lightning splits the sky in a storm. How is it like the car door shock?

    • Both are protons jumping between clouds
    • Both need a metal rod to start
    • Both are air conducting in a huge field

  8. A learner writes that rubbing created new charge on the balloon. What is the mistake?

    • Electrons are heavier than protons
    • No charge was made, it only moved
    • Static only works in dry rooms
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Answer key

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

Charge, fields, and the spark W1-mt_6ii6CVOTI5-s1

  1. True · That pair of rules drives every static effect.
  2. Electrons · Rubbing shifts electrons only; protons stay locked in nuclei.
  3. Away from it · Lines start on positives, so arrows leave the charge.
  4. Built up charge makes a fierce field across a small gap, so air conducts · A huge field across a tiny gap breaks air down into a conductor.
  5. The field is strong there · Crowded lines mean a strong field in that region.
  6. Insulators trap shifted charge, while metals let it flow away · Insulators hold the imbalance in place; metals drain it away at once.
  7. Both are air conducting in a huge field · Both are sparks: a huge voltage across a gap forcing air to conduct.
  8. No charge was made, it only moved · Charge is never created by rubbing; it only separates into matching pairs.
Worksheet · LightMySky