UNITS- Q uestion you need ton first understand the meaning of science. Science means MEASUREMENTS. In every field of science we do measurements, science only cares about measuring things. That means the things have to be observable. That’s why in science we don’t take care about FEELINGS. Because we can’t measure feelings. Now as we measure something, we need to represent it in some notation to identify or distinguish between quantities. Because whatever we measure it’s just number, if I say you the speed is 5. What info can you tell about 5, it’s just a number, it nothing tells you about anything related to speed. So you need to specify specific quantities to extract info. Actually speed refers to unit distance travel in unit seconds. So the unit distance can be shown in centimeters, meters, and kilometers. Generally we show distances in meters because it acceptable internationally and it is general notation we use in physics. So the (SI) unit of speed is meters per second. So, yo