Understanding types of charges in Some Natural Phenomena – Class 8 Science Experiment

Chapter Name: Some Natural Phenomena

Activity Name: Understanding types of charges in Some Natural Phenomena

Activity Description:

Required Items:

1. Two balloons
2. Woollen cloth
3. Two refills (or pens)
4. Polythene sheet
5. Plastic tumbler

Step by Step Procedure:

Activity 1:

1. Inflate both balloons and tie them securely.
2. Hang the balloons in a way that they do not touch each other.
3. Rub both balloons with the woollen cloth.
4. Release the balloons without touching them with your hand.

Activity 2:

1. Take one refill and rub it with the polythene sheet.
2. Place the rubbed refill gently in the plastic tumbler.
3. Take the second refill and rub it with the same polythene sheet.
4. Bring the second rubbed refill near the first one in the tumbler without touching the rubbed portions.
5. Observe any effects on the first refill in the tumbler.
6. Note if the refills attract or repel each other.

Experiment Observations:

Activity 1:

• When rubbed with the woollen cloth and released, both balloons may exhibit a similar behavior, either attracting or repelling each other.

Activity 2:

• The first rubbed refill in the tumbler may show some response when the second rubbed refill is brought near, either attracting or repelling each other.

Precautions:

1. Make sure the balloons are securely tied to prevent them from flying away.
2. Avoid touching the balloons with your hand after rubbing them with the cloth.
3. Handle the refills and balloons gently to prevent any damage.

Lesson Learnt from Experiment:

Through these activities, we can observe that objects acquire different types of electric charges (positive or negative) when rubbed with certain materials. Like charges repel each other, and opposite charges attract each other.