Like charges repel and opposite charges attract.

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

• Electrons
• Protons
• Neutrons

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

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

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

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

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

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

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