Current and voltage coils and modem: what they have in common
- Step 1. Current and voltage coils — is part of — Electricity meter. They create fields proportional to current and voltage.
- Step 2. Electricity meter — has part — Permanent magnet. A braking magnet.
- Step 3. Permanent magnet — is part of — Loudspeaker. A permanent magnet.
- Step 4. Loudspeaker — is part of — Telephone. The earpiece reproduces the other person’s voice.
- Step 5. Telephone — is used in — Modem. It works over a telephone line.