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A Car Travelling at 60 Km/H Overtakes Another Car Travelling at 42 Km/H. Assuming Each Car to Be 5.0 M Long, Find the Time Taken During the Overtake and the Total Road Distance Used for the Overtake.

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प्रश्न

A car travelling at 60 km/h overtakes another car travelling at 42 km/h. Assuming each car to be 5.0 m long, find the time taken during the overtake and the total road distance used for the overtake.

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उत्तर

Velocity of the first car, v1 = 60 km/h = 16.7 m/s
Velocity of the second car, v2 = 42 km/h = 11.7 m/s
Relative velocity between the cars = (16.7 − 11.7) = 5 m/s
Distance travelled by the first car w.r.t. the second car = 5 + 5 = 10 m
Time,

\[t = \frac{s}{v} = \frac{10}{5} s\] = 2 s
Distance covered by the first car w.r.t. the ground in 2 s = 16.7 × 2 = 33.4 m
The first car also covers a distance equal to its own length = 5 m
∴ Total road distance used for the overtake = 33.4 + 5 ≈ 38 m

 

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अध्याय 3: Rest and Motion: Kinematics - Exercise [पृष्ठ ५२]

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एचसी वर्मा Concepts of Physics Volume 1 and 2 [English]
अध्याय 3 Rest and Motion: Kinematics
Exercise | Q 22 | पृष्ठ ५२

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