1) Smoke Precipitators..
- As smoke particles reach the bottom of the chimney, they meet a wire grid with a high negative charge and this charges the smoke negatively.
- The charged smoke particles are attracted to positively charged metal plates. The smoke particles stick together to form larger particles.
- When heavy enough, the particles fall off the plates or are knocked off by a hammer. The dust falls to the bottom of the chimney and can be removed.
- The gases coming out of the chimney have very little smoke in them.
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- The image plate is positively charged. An image of what you're copying is projected on to it.
- Whiter bits of the thing you're copying make light fall on the plate and thecharge leaks away in those places.
- The charged bits attract negatively charged black powder, which istransformed onto positively charged paper.
- The paper is heated so the powder sticks.
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