Static Electricity Quiz

Anika has two balloons, and she holds them close to each other. Nothing happens. She is disappointed because she has seen so many YouTube videos where the balloons push each other away. Why does this not happen to her balloons?

• The balloons have not undergone any friction, therefore do not have a charge.

• The balloons are neutral; they have an equal number of electrons and protons.

• The balloons have no spare protons.

• The balloons are neutral; they have more electrons and protons.

Answer explanation

A neutral object has an equal number of electrons and protons, which balance each other out, resulting in no overall charge. This is why Anika's balloons remain still and unaffected by each other. In order for them to gain a charge they will need to undergo friction.

Mason and Mpho are playing with a balloon and decide to rub it against Mason's hair. After rubbing, the balloon (insulator) becomes negatively charged.

What happens to the atoms in the balloon that causes this negative charge? The balloon (a)   .

• loses neutrons
• gains protons
• loses electrons
• gains electrons

Answer explanation

The balloon becomes negatively charged because it gains electrons. Electrons are negatively charged, so when they are added, the balloon has a net negative charge. A balloon is also made of an insulator, which is much more likely to gain electrons than give them away.

You see a demonstration of static electricity. Olivia rubs a balloon on her hair and then uses it to pick up small pieces of paper. This happens because the balloon has gained a charge. The unit of charge that describes electric charge is the (a)   .

• Ampere

• Volt

• Ohm

• Coulomb

Answer explanation

The balloon gains a charge when rubbed on hair, allowing it to attract small pieces of paper. The unit of electric charge is the Coulomb, which quantifies the amount of charge the balloon has acquired.

You rub a balloon against a sweater. When you bring the balloon close to small pieces of paper, they jump towards the balloon. What is happening in this situation?

The balloon must be ​ ​ (a)   because it has undergone ​ (b)   with the sweater. The pieces of paper are ​ (c)   by the balloon, meaning the paper is either ​ (d)   or positively charged.

• repelled
• ignored
• dispersed
• attracted
• neutral
• friction
• positively charged
• negatively charged

Answer explanation

The balloon becomes negatively charged by gaining electrons from the sweater. When brought near paper, the positive charges in the paper are attracted to the balloon, causing the paper to jump towards it. This illustrates the rapid transfer of electrons.

Hannah is working on a science project about electricity. She learns about insulators. What do these materials do?

• Conduct electricity efficiently.

• Enhance the flow of electricity.

• Resist the flow of electric charge.

• Allow electric charge to move freely.

Answer explanation

Materials that resist the flow of electric charge are known as insulators. They prevent electricity from flowing easily, unlike conductors, which allow electric charge to move freely. The atoms in insulators have strong bonds with their electrons, and they do not move freely. Remember, electrons are the only sub-atomic particles that can move.

Anika has two balloons that she rubs on her hair. After rubbing, she brings them close to each other, and something happens. How will Anika's balloons respond?

The balloons will ​ (a)   each other.

Why will they respond this way?

Both balloons experienced ​ (b)   with the same material (hair), which means that they will have ​ (c)   and therefore ​ (d)   .

• repel
• attract
• friction
• like charges
• unlike
• neutral
• push each other away
• move towards each other.

Answer explanation

The two balloons are both rubbed on Anika's hair. This means that the election movement will be the same, and this means they will have a like charge. We can guess that it will be a negative charge because the balloons are an insulator, and hair is a natural substance and more likely to give electrons away.

Instead of using coulombs at a grade 8 level, we simplify the magnitude and polarity of charges as follows:

An electron has a charge of (a)   and a proton has a charge of ​ (b)   .

• +0
• 0

• -1
• 1
• +1
• -0

Answer explanation

Each electron and proton has the same magnitude of charge, which is 1. The polarity of the charge is different. Electrons are negative (-1) and protons(+1) are positive.

Betty wants to know what happens when she rubs a balloon on her hair. What happens as a result of this friction?

• Betty's hair is part of her body and we know that people and animals are conductors, the hair is going to give away electrons.

• The balloon is an insulator and holds onto its protons and electrons and gains electrons.

• Nothing is going to happen with the friction.

• The friction will result in a neutral state being created for the hair and the balloon.

Answer explanation

When Betty rubs the balloon on her hair, electrons are transferred from her hair to the balloon, causing the balloon to gain electrons while retaining its protons. This results in a negatively charged balloon.

Aria is walking across a carpet on a dry day, and she touches a metal doorknob, her hand shoots back, and she feels pain. What happened to cause this?

• An electrostatic discharge.

• A continuous flow of electricity.

• A change in temperature.

• A permanent charge.

Answer explanation

When Aria touches the metal doorknob, the built-up static electricity discharges, resulting in a small shock or spark. This is a quick release of energy, not a continuous flow or permanent charge.

Match the following types of materials with their properties related to electric charge movement.

• insulators

• Materials that resist electric charge

• semi-conductors

• Materials that are have no charge

• neutral

• Materials that allow electric charge to move freely

• conductors

• Materials that do not conduct electricity