Calculating the Speed of a Plane for a Stationary Sun at 26.3° Latitude

AI Thread Summary
To calculate the speed of a plane at 26.3° latitude so that the sun appears stationary to passengers, one must consider the Earth's rotation and the radius of the circular path at that latitude. The period of rotation is 24 hours, and the radius can be determined using the Earth's radius and the cosine of the latitude angle. By applying the formula for linear speed (v = 2πr/T), where T is the period in seconds, the necessary speed can be calculated. A free-body diagram is not essential for this calculation, but it can help visualize the problem. Ultimately, the discussion emphasizes the relationship between circular motion and the Earth's rotation in determining the required speed.
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Homework Statement



How fast must a plane fly at a latitude of 26.3° so that the sun stands still relative to the passengers?

Homework Equations



I have no idea how I can solve this question. I would like to draw a free-body diagram, but I don't know how to do that either. If I could at least draw a diagram, it would help me to think through this question.

The Attempt at a Solution



I believe that the plane is 26.3 degrees above the equator, flying around the earth. So it is a circular motion question.

I don't have an acceleration, now do I have a period, but I think that the period might be one rotation around the earth, so 24 hours is one period? Also, the radius of the Earth is 6.37e6 m. angular velocity = speed/radius and angular velocity = 2pi/period
 
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You indeed have a period of 24 hours.

The radius of the circle at a latitude of 26.3 degress is the distance from the Earth's axis to any point of this circle.
draw a picture of a crosssection through the Earth along the Earth's axis.
 


Thank you! I drew the free body diagram, found the radius using 6.37x10^6 cos 26.3 deg. and then substituted the radius and the period (T) --> (24hours = 86400 sec) into v= 2pir/T and got the answer :)
 


Why do u need to know the freebody diagram?
 
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