# Maths or physics Interception question

1. Aug 23, 2004

### High_flier

Two airports (A and B) are 200nm apart. Aircraft 1 leaves airport A and
flies to B at 100kts. Aircraft 2 leaves airport B and flies to A at 200kts.
Both aircraft leave at the same time, where relative to airport A will they
pass each other?

nm=nautical miles
kts=kts

2. Aug 24, 2004

### Staff: Mentor

Here's one way to solve this. Call the time at which they pass each other t. During that time, each flies a certain distance D = V t. So aircraft 1 travels a distance $D_1 = V_1 t$ and aircraft 2 travels a distance $D_2 = V_2 t$. But the total distance traveled by both aircraft must equal the distance between A and B (200 nm). I'll leave the next step to you: set up the equation and solve for t, then plug t in to solve for $D_1$.

Once you understand what's happening, you can practically do this problem in your head. Realize that the distance each aircraft travels is proportional to its speed. Aircraft 1 travels half as fast as aircraft 2, so it travels half the distance of aircraft 2. If aircraft 1 travels D, aircraft 2 travels 2D. The total is 3D = 200 nm. Solve for D.