What is Uniform motion?
A motion at a constant speed is called Uniform motion.
For uniform motion, if the constant distance covered for each time period and the total time duration of motion are known, then we can calculate the total distance covered.
𝑇𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑐𝑜𝑣𝑒𝑟𝑒𝑑= 𝐶𝑜𝑛𝑠𝑡𝑎𝑛𝑡 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑐𝑜𝑣𝑒𝑟𝑒𝑑 (𝑓𝑜𝑟 𝑒𝑎𝑐ℎ 𝑡𝑖𝑚𝑒 𝑝𝑒𝑟𝑖𝑜𝑑) × 𝑇𝑜𝑡𝑎𝑙 𝑡𝑖𝑚𝑒 𝑑𝑢𝑟𝑎𝑡𝑖𝑜𝑛
Consider an example of uniform motion – A man is running at a constant speed of 3 m/s and runs for 1 minute = 60 s.
From this we can calculate the total distance covered by the man –
𝑇𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑐𝑜𝑣𝑒𝑟𝑒𝑑 = 3 𝑚/𝑠 × 60 𝑠 = 180 𝑚
Speed – Distance travelled by an object in unit time is called Speed.
𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒
𝑆𝑝𝑒𝑒𝑑 = 𝑈𝑛𝑖𝑡 𝑡𝑖𝑚𝑒
The SI unit of speed is metres per second (m/s). Speed can also be denoted in centimetres per second (cm/s), miles per hour (mi/h) or kilometres per hour (km/h).
What is Non-uniform motion?
When the motion of an object is not at a constant speed, it is called Non-Uniform motion.
A few examples of non-uniform motion are walking, running, riding a bicycle or driving a car. In these activities, a uniform speed cannot be maintained due to external factors such as traffic, traffic lights, busy crowded areas, etc.
Non-uniform motion examples
Average speed – For an object in non-uniform motion, the total distance covered divided by the total time elapsed is the Average speed.
𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝑆𝑝𝑒𝑒𝑑 =𝑇𝑜𝑡𝑎𝑙 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑐𝑜𝑣𝑒𝑟𝑒𝑑/𝐸𝑙𝑎𝑝𝑠𝑒𝑑 𝑡𝑖𝑚𝑒
Instantaneous speed – When the speed of an object is not constant, the speed at any instant is called Instantaneous speed.