REMINDER

A train is moving at a constant speed of 75 km/h . Draw a distance - time graph find from your graph.

i) How much distance will the train cover in 13 hours 20 minutes.

ii) How long will the train take to cover a distance of 187.5 Km ?

Answer :

We have constant speed =  75 km / hr

Now we draw Distance  - time graph , AS :


1 ) Here From the graph , We can see that  Total distance covered  =  1000 km

We can also check our solution from formula , As

We know Distance =  Speed $\times$ Time ,
So,

Total distance covered in 13 hr 20 minutes (  13 + $\frac{20}{60} = 13 + \frac{1}{3} = \frac{40}{3}$ )  hr  = 75 $\times$ $\frac{40}{3}$  =  1000

So,

Total distance covered in 13 hr 20 minutes  =  1000 km  ( point C represent on graph )


2 ) From the graph , we can see that at 2.5 hr ,train will cover nearly 200 km  .

But we can find exact value from our formula , As :

We know Time  = $\frac{Dis\tan ce}{Speed}$

So,

Train take time to cover 187.5 km  = $\frac{187.5}{75}$  = 2. 5

So,

Train will take 2. 5 hr to cover 187.5 km  .  ( point B represent on graph )