Same chapter3 marksDifficulty: Medium
A body is thrown vertically upwards with a speed of 30 m s−1. Find the maximum height it reaches and the time it takes to return. Take g = 10 m s−2.
Kinematics
3 marksDifficulty: Medium
Distinguish between average velocity and instantaneous velocity.
Original Khojo Papers practice question — not from a past board paper.
Answer
Average velocity is the total displacement divided by the total time taken, so it describes the whole journey. Instantaneous velocity is the velocity at a particular moment, the limit of the average velocity as the time interval tends to zero, and it is the derivative of displacement with respect to time.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The speedometer of a car reads its instantaneous speed.
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