Dial with pointer and headphones: what they have in common

1. Step 1. Dial with pointer — is part of — Kitchen scale. A weight indicator.
2. Step 2. Kitchen scale — has part — Spring. The load stretches a spring.
3. Step 3. Spring — is part of — Pinball. A plunger.
4. Step 4. Pinball — has part — Electromagnet. Flippers are solenoids.
5. Step 5. Electromagnet — works like — Permanent magnet. An electromagnet attracts iron like a permanent magnet, but only while current flows.
6. Step 6. Permanent magnet — is part of — Headphones. A magnet moves the diaphragm.

Open Evothings