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Question
When extremely small particles X derived from the anther of a flower were suspended in a liquid Y and observed through a microscope, it was found that the particles X were moving throughout the liquid Y in a very zig-zag way. It was also observed that warmer the liquid Y, faster the particles X moved on its surface.
- What could particles X be ?
- What do you think liquid Y is ?
- What is the zig-zag movement of X known as ?
- What is causing the zig-zag movement of particles X ?
- Name the scientist who discovered this phenomenon.
- What does this experiment tell us about the nature of liquid Y?
Solution
The particles, 'X' are pollen grains.
- The fluid, 'Y' is Water.
- The zigzag movement of 'X' is called Brownian motion.
- The zigzag motion of the pollen grains occurs because the particles of water are in constant motion. These particles collide with the pollen grains and cause them to move.
- Robert Brown is the scientist who discovered Brownian motion.
- Liquid Y is made up of extremely small particles, which are moving constantly.
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