What is the angular velocity of an aircraft passing overhead at 900 km/h?

haxan7
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Homework Statement


An aircraft passes directly over you with a speed of 900 km/h at an altitude of 10,000 m. What is the angular velocity of the aircraft (relative to you) when directly overhead? Three minutes later?

Homework Equations


Where were studying center of mass and Moment of inertia.

The Attempt at a Solution


No idea, how to approach this question, Aircraft is flying straight, will there even by any angular velocity?
 
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Draw a straight line from your eye to the aircraft. It changes direction as the aircraft flies over you, does not it? The line encloses an angle alpha with the vertical. Find the expression for this angle in terms of time. The angular velocity is the time derivative of the angle.

ehild
 
ehild said:
Draw a straight line from your eye to the aircraft. It changes direction as the aircraft flies over you, does not it? The line encloses an angle alpha with the vertical. Find the expression for this angle in terms of time. The angular velocity is the time derivative of the angle.

ehild

Speed = 900km/hour
tan(α)=900t/10000
α=arctan(900t/10000)

Derivative is 900/(10000+81 t^2)
If i put t = 0 and t = 3/60, will i get the correct answer? I don't think so, Help me.
 
Last edited:
Do not mix units. Convert the speed of the aircraft to m/s.

ehild
 
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