Physics - Conductive and Inductive

Charging by Induction
- No physical contact is made between charged objects and neutral objects.
- Requires at least three objects to facilitate electron movement.
- Example: When a charged object A is brought close to objects B and C, it induces a charge in them by pushing electrons.
- B and C must touch initially for the charge to be transferred effectively.

Ground as a Charge Reservoir
- The Earth can absorb or supply electrons as needed, acting as a third object.
- Common grounding methods include connecting wires to water pipes or copper rods driven into the ground to safely divert excess charge.
- This helps protect against electrical shocks by re-directing electricity away from hazards.

Charging by Friction
- Example: Rubbing a plastic rod with fur charges the rod negatively; the fur becomes positively charged as it loses electrons.
Charging by Conduction
- Occurs when two charged objects come into contact and share charge based on their respective charges.

Charging Calculations
- If a plastic rod receives a charge of -1.36 x 10^-16 coulombs from friction with fur:
  - To find the number of elementary charges transferred:
    - Divide
      - (-1.36 x 10^-16 C) / (1.6 x 10^-19 C/electron) = 850 electrons transferred.
  - Charge on the fur would be +1.36 x 10^-16 coulombs.
- Key Points
  - Fur loses electrons.
  - Rod gains electrons.
Identifying Charging Type
- Distinction between conduction and induction based on whether objects make contact.