How to Calculate Relative Velocity in Wind for a Plane and Cyclist?

AI Thread Summary
To calculate relative velocity for the aircraft and cyclist, the aircraft's speed in still air is 300 km/h, and it encounters a wind of 140 km/h from a bearing of 230 degrees while flying due east. The pilot must determine the course to compensate for the wind, and the time to travel 100 km can be calculated using vector addition. For the cyclist, who travels east at 18 km/h, the wind appears to blow at 12 km/h from a bearing of 150 degrees, requiring the determination of the true wind speed and direction. A vector diagram can be drawn to visualize the relationships between the plane's speed, the wind's speed, and the resultant ground speed. Understanding these concepts is crucial for accurately calculating the effects of wind on both the aircraft and cyclist's velocities.
Zoheb Imran
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a,The Speed Of an aircraft in still air is 300 km/h.
In a wind of speed 140 km/h, blowing from a bearing of 230, the aircraft flies due east. Find
i, the course set by the pilot
ii, the time taken for the aircraft to travel 100 km.

b,To a cyclist traveling due east at 18 km/h the wind appears to be blowing at 12 km/h from a bearing of 150. Find the true wind-speed and the direction from which the wind is blowing.
 
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how to draw a vector diagram ?? of the above problem?? I only have problem in that...
 
its all simple trigonometry ... after that... i need to know what will be the direction of Aircraft in still air? what does that mean? what will be the direction of of wind... how will we create a vector diagram...of it?
 
You should be able to draw 3 vectors, where one of them is the final speed and direction of the moving object(which you can find by vector addition).
 
Zoheb Imran said:
how to draw a vector diagram ?? of the above problem?? I only have problem in that...

Hi Zoheb! :smile:

Give them letters!

Call the plane P, the air A, and the ground G.

Then P - A = 300, and A - G = 140 @ 230º.

And you know that P - G is 90º.

Draw a triangle with an arrow on each side, so that the arrow along P - A goes the same way as the arrow along A - G (in other words, it doesn't meet it head-on).

Does that make sense? :smile:
Zoheb Imran said:
… what will be the direction of Aircraft in still air?


Not relevant … in still air, it would go at 300 in any direction … they're simply telling you how powerful the aircraft is.
 
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