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Hello, we have to solve the following problem.
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Model plane has a mass of 0 .75 kilograms.
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And this model plane is tightened to the cord, and another end of this cord is tightened to the ground.
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Length of the cord is 33 meters, and the plane is at the height of 18 meters above the ground.
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It makes 4 .4 revolutions per minute, and the lift is perpendicular to the unbanked wings.
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First of all, we have to calculate acceleration.
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Let's do this.
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It means that we have to draw this system.
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Let's show the axis, axis y.
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And now we will show this chord and the plane.
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The plane experiences gravity, the lift, and also tension in the cord.
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And overall, it results in the centripetal force to the level.
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The center.
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Now let's label the distances.
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Court has a length of l and it's located at the height of h.
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Now let's calculate this angle alpha.
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This angle alpha is a sign of h over l.
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That is 33 degrees.
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Therefore, acceleration is omega squared times radius and here radius is the bottom cutt of the triangle.
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Which is omega squared times l times cosine alpha.
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Here we have to convert rotation rate from revolutions per minute to radiance per second...