Two commuter rail cars, one from shah alam and the other from kuala lumpur approach each other on parallel tracks. each has a speed of 100km/h with respect to the earth. if they are initially 10km apart, how long will it be before they pass each other?

They meet after the time t from the departure

During this time, one goes through the distance

S1 = V1 * t

and the second goes through the distance

S2 = V2 * t

The sum of the two distances gives us total distance

S1 + S2 = S

Replace S1 and S2 in this last equation

V1 * + V2 * t = S

t (V1 + V2) = S where we take out the time they meet

t = S / (V1 + V2)

V1 = V2

t = 10 / 2V1 = 10/200 = 0.05 hours

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.

dopamine..

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