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Question
A passenger arriving in a new town wishes to go from the station to a hotel located 10 km away on a straight road from the station. A dishonest cabman takes him along a circuitous path 23 km long and reaches the hotel in 28 min.
- What is the average speed of the taxi,
- the magnitude of average velocity? Are the two equal?
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Solution
(a) Total distance travelled = 23 km
Total time taken = 28 min
= `28/60` h
∴ Average speed of the taxi = `"Total distance travelled"/"Total time taken"`
= `23/(28/60)`
= 49.29 km/h
(b) Distance between the hotel and the station = 10 km = Displacement of the car
∴ Average velocity = `10/(28/60)`
= 21.43 km/h
Therefore, the two physical quantities (average speed and average velocity) are not equal.
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