Charged objects- progress learning

You rub a balloon on your head and it becomes negatively charged. The balloon will be MOST attracted to

• a piece of metal.

• positively charged hair.

• the neutrally charged wall.

• another negatively charged balloon.

Answer explanation

The negatively charged balloon is attracted to positively charged hair due to opposite charges attracting each other. In contrast, it would repel another negatively charged balloon and have a weaker attraction to neutral objects.

Tags

NGSS.MS-PS2-3

An ebonite (very hard, black rubber) rod is rubbed with the four different substances below. Choose the one that is MOST likely to produce the largest static charge by friction.

• fur

• paper

• silk

• wax

Answer explanation

Fur is known to produce a significant static charge when rubbed against materials like ebonite due to its high electron affinity. This makes it the most effective choice among the options listed for generating static electricity.

Jermaine and Lashonda each rub their dry hair with inflated balloons. While doing this, the other students notice that their hair is starting to stick straight out.

Next, the teacher takes the balloons and places them right next to one another. However, the balloons will not stay next to each other, as they normally would. Instead, they spring apart in opposite directions. Explain what is causing these balloons to push each other away.

• There must be a vent in the classroom blowing the two balloons apart.

• They have each gained negative charge from the hair rubbing, and like charges repel each other.

• They have each gained negative charge from the hair rubbing, and like charges attract each other.

• The rubber balloons are simply bouncing off each other the way a rubber ball bounces off the floor.

Answer explanation

The balloons gain negative charge from rubbing against hair, resulting in like charges. Since like charges repel each other, the balloons push apart instead of staying next to each other.

Tags

NGSS.MS-PS2-3

What type of energy occurs when a sock is stuck to a blanket when it is taken out of the dryer?

• current electricity

• static electricity

• heat energy

• high voltage electricity

Answer explanation

When a sock is removed from a dryer, it can become charged due to friction with the blanket, leading to attraction. This phenomenon is known as static electricity, which is the correct answer.

What would be a result of this simple static electricity experiment? Rubbing the balloons against the woolen fabric or your hair creates static electricity. This involves negatively charged particles (electrons) jumping to positively charged objects. When you rub the balloons against your hair or the fabric they become negatively charged, they have taken some of the electrons from the hair/fabric and left them positively charged.

• Both your hair and the balloon would be negatively charged and static would cause them to separate.

• Rubbing the balloons against the woolen fabric or your hair creates heat energy.

• Your positively charged hair would be attracted to the negatively charged balloon and would rise up to meet the balloon.

• Static electricity is the movement of the charged particles between the objects.

Answer explanation

When you rub the balloon, it becomes negatively charged by gaining electrons. Your hair loses electrons and becomes positively charged. Thus, the positively charged hair is attracted to the negatively charged balloon, causing it to rise.

Tags

NGSS.MS-PS2-5

One type of static electricity is the lightning in a thunder and lightning storm. Clouds become negatively charged as ice crystals inside the clouds rub up against each other. Meanwhile, on the ground, the positive charge increases. The clouds get so highly charged that the electrons jump from the ground to the cloud, or from one cloud to another cloud. This causes a huge spark of static electricity in the sky that we call lightning. Which simple experiment could be conducted to show an example of how lightning is created?

• Rub a balloon so it picks up extra electrons from the sweater or your hair and becomes slightly negatively charged.

• Rub a balloon filled with air on a wool sweater or on your hair. Then, hold it up to a wall.

• Connect the positive pole of an electrical source to the negative pole so you create a circuit.

• Walk across a carpet, shuffling your feet and touching something made of metal.

Answer explanation

Walking across a carpet and shuffling your feet builds up static charge, similar to how clouds become charged. Touching metal releases this charge, mimicking the discharge of lightning.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

Sarah is learning about human-harnessed electricity as well as naturally-occurring electricity. Sarah comes in contact with many forms of electricity each day. Which is an example of Sarah coming in contact with naturally-occurring electricity?

• Sarah walks quickly across the carpet in socks and feels a small shock when she touches the doorknob.

• Sarah felt a small sting on her finger when she changed the light bulb on her lamp.

• Sarah was lightly shocked when she inserted the plug of her lamp in the wall socket.

• Sarah accidentally left her curling iron plugged in and burned her hand on the metal.

Answer explanation

The correct choice is when Sarah walks quickly across the carpet and feels a shock from the doorknob. This is an example of naturally-occurring electricity, specifically static electricity, generated by friction.

A child touched a doorknob and experienced a strong shock. What explains in terms of electricity why this child received a noticeable shock?

• She was wearing leather gloves.

• She was wearing clothing made of wool.

• She shuffled her feet across the carpet.

• She walked from the rug to the tile floor.

Answer explanation

The child shuffled her feet across the carpet, generating static electricity. When she touched the doorknob, the built-up charge discharged, causing a noticeable shock.

Tags

NGSS.MS-PS2-5

Which diagram best shows how the balls will react after becoming charged?

• Balls move apart

• Balls move together

• Balls remain in place

Answer explanation

When balls become charged, like charges repel and opposite charges attract. If the balls are oppositely charged, they will move together, demonstrating attraction. Thus, the correct answer is that the balls move together.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

You have a positively charged glass rod and a negatively charged plastic straw. What will happen if you bring them close to each other?

• They will repel each other.

• They will attract each other.

• Nothing will happen.

• They will both become neutral.

Answer explanation

The positively charged glass rod and negatively charged plastic straw will attract each other due to opposite charges. This attraction occurs because opposite charges exert a force on each other, leading to a pull.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5