Question

a train with a constant speed of 60km/h goes east for 40min. then it goes 45 degrees northeast for 20min. and finally, it goes west for 50 min. what is the average velocity of the train?

Answer 1

Answer:

$\left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] \left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] \left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] \left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right] \left[\begin{array}{ccc}1&2&3\\4&5&6\\7&8&9\end{array}\right]$

Explanation:

Let X be the distance between A and B

initial time = X / 60

final time = X / 40

so, total time = X / 24

average speed = 2x / (X/24)

= 48 km/h

average velocity is zero since, displacement is zero.