Science 7
3rd Quarter (Week 7-8)
Lesson 1: Charging by Friction
All materials, including you, are made up of atoms. Atoms in turn are made up of
even smaller building blocks – electrons, protons, and neutrons.
Activity 1: What’s My Charge? ⚡➕➖💡
Directions: Copy the illustration in your Science activity notebook. Identify the
appropriate atomic particle charge by drawing a line from the particle to its corresponding
charge.
Activity 2: Charged Party! 🎈🎆🎈⚡
Materials: 2 balloons 2 strings (0.5 meters each) mirror
Procedure:
1. Inflate the two balloons and tie each with a string.
2. Rub 1 air-filled balloon vigorously across your completely dry hair for
at least 1 minute.
3. Face the mirror and hold the balloon close to your hair. Was your hair pulled by the
balloon?
4. Now rub two air-filled balloons vigorously across your completely dry
hair for at least 1 minute.
5. Hold the balloons by the string (it should be hanging down) and then
gently bring them near each other. Observe any interaction.
Answer the following questions in your Science activity notebook.
1. What happens when you bring the balloon near your hair after rubbing it?
__________________________________________________________
2. What about bringing the two rubbed balloons near each other?
_____________________________________________________
3. What do you think is the cause of these interactions?
_____________________________________________________
Lesson 2: Charging by Induction
Activity 1: Attract or Repel? ➕➖▶◀❔
Directions: Copy the table in your Science activity notebook. Identify the interaction of the
following pair of charges by putting a check ( ) mark in each corresponding column.
Lesson 3: Charging by Conduction