# Homework Help: Aeroplane problem!

1. Jan 19, 2008

### Cathartics

[SOLVED] Aeroplane problem!

A pilot flies horizontally at 1350 km/h, at height h = 50 m above initially level ground. However, at time t = 0, the pilot begins to fly over ground sloping upward at angle θ = 4.3°. If the pilot does not change the airplane's heading, at what time t does the plane strike the ground?

Here is what i tired to do

I took tan4.3 = 50/x and found x =664.98 and then tried to find time(t) by using this formula
x = ((v1-v2) * t / 2 ) where v1 = initial velocity and v2 = final velocity but when i plug em up online they tell me it's wrong. Please help!!!

2. Jan 19, 2008

### Shooting Star

The velocity of the plane is constant. Just use x=vt.

3. Jan 19, 2008

### Tom Mattson

Staff Emeritus
That part is fine.

Think about it for a second. The velocity isn't changing. That means that the initial and final velocities must be the same. All you have to do is figure out how long it takes the plane to travel 664.98m at 1350 km/h (watch your units - the distance is in m, but the speed is in km/h).

4. Jan 19, 2008

### Cathartics

Many thanks!

Thanks shooting_star, I got that right. And thank you tom for that info but x=vt did the trick...

5. Jan 20, 2008

### Shooting Star

Tom wanted to you arrive at the x=vt through some logic, which would have helped you the next time. I do hope you know why or how or when we use that formula.