00:02
In this question we're giving that there is a car moving with a speed 95, so v car, equal to 95 km per hour, and passing a train, the train of length equal to 1 .3 km, moving parallel to the car, where the speed is 75 v train, 75 km per hour.
00:42
And this question has a couple of few parts.
00:47
One is how long does it take the car to pass the train, and then how far would the car travel in this time? and then what will be the answers of the directions of the current train has been reversed? they go in opposite, sorry, what's going to be the answers if they go in opposite directions, not the same direction.
01:09
So the first part, which is how long does it take the car to pass the train, we're looking for time for the car to pass the train.
01:18
So here if you are in the train, you're going to see the car moving with a speed 95 minus 75 kilometers per hour.
01:26
It's called the relative speed.
01:28
So the relative when you are in the train, frame going to be 95 km per hour minus the 75 kilometer per hour and that will give you 20 kilometer per hour and for the car to travel a distance of the train length it's going to take time equivalent to the distance of the train the length of the train divide by better of speed which is the 20 kilometer per hour and this time will be about 0 .06 5 hours in terms of minutes going to be 3 .9 minutes okay two significant figures that's for the first part the second part she's asking how long how far the car have traveled in this time so distance of traveled by the car is equal to the speed of the car times the time it took to pass the train, just 3 .9.
02:47
Sorry, this is not...
02:49
The unit here is wrong, my apology...