Question
Mention two units for each for measuring objects of size (i) very large (ii) very small. Why do you require units of different sizes?
Answer
- Two units for measuring objects of a size that are very large are kilometres (km) and astronomical units (AU). Kilometres are used for measuring distances on Earth, while astronomical units are used to measure distances between celestial objects.
- Two units for measuring objects of a size that are very small are nanometers (nm) and angstroms (Å). Nanometers are used to measure the size of small particles such as atoms and molecules, while angstroms are used for measuring atomic and molecular distances.
Units of different sizes are required because different objects or phenomena have vastly different sizes and scales. For example, the size of an atom is much smaller than the size of a cell, which is much smaller than the size of a human, and so on. Using the appropriate unit of measurement allows us to express these sizes in a meaningful way that is appropriate for the scale of the object or phenomenon being measured.