Question

A train takes 2 h to reach station B from station A, and then 3 h to return from station B to station A. The distance between the two stations is 200 km. Find (i) The average speed (ii) The average velocity of the train

February 16, 2024

Answer

Distance travelled S₁ = 200 km

time t₁ = 2 h

Distance travelled S₂ = 200 km

time t₂ = 3 h

(i) Total distance travelled (S) = S₁ + S₂

= 200 km + 200 km = 400 km

Total time taken t = t₁ + t₂

= 2 h + 3 h = 5 h

Average Speed = 400/5 = 80 km h^-1

Hence, Average speed of the car = 80 km h^-1

(ii) Displacement = 0 (since final position is same as initial position)

Hence, Average velocity = 0 ( as displacement = 0)

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