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Hi great nls Pls help me out of this question.Pls i need explanation and tips on how to solve similar question.the question goes thus: . Two goods train each 500 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one. A. 12 sec B. 24 sec C. 48 sec D. 60 sec

Your question is structured incorrectly. You need to clarify one issue. Take a look at the representations of the problem below. The letter D represents the train driver. Which of the configuration below best describes your question?

DCCCCCCCCCCCCCCCCCCCCCC Fast train --->
<--- DCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC Slow train

Configuration A.


DCCCCCCCCCCCCCCCCCCCCCC Fast train --->
<---- CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCD Slow train

Configuration B.

Took the liberty of solving without waiting for your input since it was not very difficult.

For configuration A, the answer is 24secs.

For configuration B, the answer is 48secs.

Solution Logic:

In a time t, slow train travels x meters. In a similar time period fast train travels (500-x) meters and (1000-x) meters respectively for configurations A and B. Using your physics equation: S= Ut + (1/2at2). Terms in brackets = 0 since no acceleration. Hence:

slow train: x=30t
fast train: (500-x)=45t or (1000-x)=45t depending on configuration.

Substitute for x and solve. Dont forget to get your units right.