Distinguish between instantaneous speed and average speed. When are they equal?
PhysicsClass 9CBSEAnswered 13 May 2026
Answer
Instantaneous speed is the speed of an object at a particular instant in time. It is what a speedometer in a car measures. It can vary from moment to moment.
Average speed is the total distance covered by an object divided by the total time taken for the entire journey.
Instantaneous speed and average speed are equal when an object is moving with uniform speed (constant speed) throughout its motion. In this case, the speed at any instant is the same as the overall average speed.
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