What do we know?
  • We know how to get a diameter, drawing a chord.
  • We know some properties of the similar rectangle triangles.
  • We can use the programm SALSAJ in order to take measurements on a picture given ¡

What do we have to find out?
  • We are asked to measure the Moon's diameter.

Work out
  • Open SalsaJ and then open the picture below:

  • Draw any line (a chord of the circumference) on the picture.
  • This line intersects the edge of the circumference on two points.
  • Measure (pixels units) the length of this line between these endpoints.
  • Divide it up into equal parts.
  • Now you can have the midpoint, M, find it helped by the programm SalsaJ.
  • Draw a perpendicular to the line through the midpoint.
  • Measure (on that line) the distance from M to the edge of the circunference of the Moon.
  • Using your knoledges related with circumference's properties, find out the Moon's diameter.
solucion_tratamiento_imagenes_ingles.txt · Última modificación: 24/04/2017 13:13 (editor externo)
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