Trucks travels beneath an airplane .

[ArcherofScience]

trucks travels beneath an airplane...

Homework Statement

A truck travels beneath an airplane that is
moving 180 km/h at an angle of 39 to the
ground. How fast must the truck travel to stay be-
neath the airplane? What is the magnitude of the vertical component of the velocity of the plane? Answer in units of km/h

Homework Equations

My physics teacher said the question is identifying the horizontal and vertical components. So I had to do Vcostheta and Vsintheta.

The Attempt at a Solution

Vcostheta=180cos39=139.8863 km/h
vsintheta=180sin39=113.2777 km/h

my problem is, I don't understand which direciton the vectors are. Is it going north of east or south of east, or what? I can't identify them in the problem and I can't tell if the answers need a negative sign or positive sign.

 

[Dick]

Homework Statement

A truck travels beneath an airplane that is
moving 180 km/h at an angle of 39 to the
ground. How fast must the truck travel to stay be-
neath the airplane? What is the magnitude of the vertical component of the velocity of the plane? Answer in units of km/h

Homework Equations

My physics teacher said the question is identifying the horizontal and vertical components. So I had to do Vcostheta and Vsintheta.

The Attempt at a Solution

Vcostheta=180cos39=139.8863 km/h
vsintheta=180sin39=113.2777 km/h

my problem is, I don't understand which direciton the vectors are. Is it going north of east or south of east, or what? I can't identify them in the problem and I can't tell if the answers need a negative sign or positive sign.

The problem is only asking you questions like "How fast" and "magnitude of". Those are questions where the answer is always positive. You can pick a direction for things to be traveling in if it helps you picture things but it shouldn't affect your answer.

 

[ArcherofScience]

ohh ok. i see. thanks :)...i have another question from my hw...is it ok to ask it on this same thread?

 

[Dick]

ohh ok. i see. thanks :)...i have another question from my hw...is it ok to ask it on this same thread?

Its ok. But it will probably get more attention if you post it in a new thread.