Question

2.

Answer 1

Answer:

Step-by-step explanation:

Assume the dish opens upwards. The cross-section through the vertex is a parabola. You know three points on the parabola: (0,0), (2,2), and (-2,2). Plug the points into y = ax² + bx + c to get a system of three equations where a=0.5, b=c=0.

Equation of parabola: y = 0.5x²

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Vertex (0,0)

Focal length = 1/(4×0.5) = 0.5

Focus (0,0+0.5) = (0, 0.5)

Directrix y = 0-0.5 = -0.5

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At endpoints of latus rectum, y = 0.5

x = ±√0.5 = ±√2/2

Focal width = 2×√2/2 = √2

:::::

Place antenna at focus, (9,2)