Models to visualize size and distance in the universe

# JOB 2: The Earth a grain of fine sand

If we continued to use the scale you set up in JOB 1 as we went past the solar system, soon the distances in your model would get too large to imagine. Let us scale everything down a bit more, then. Instead of the earth being the size of the E ball, let the Earth be represented by a grain of fine sand, the size of the A ball, with a diameter of ¼mm.

 Step 1. Establish a scale for your JOB 2 model Make a ratio of the actual diameter of the Earth to the diameter of the model of the Earth (Be sure units are the same in the numerator and denominator before canceling them) SCALE = [1.2x107m] / [0.25 x 0.001m]   =   [4.8x1010] : [1]

 The SCALE of this model is: [4.8x1010] : [1] The Scale factor is 4.8x1010

In your JOB 2 scale model, the size of the Earth will be the size of a grain of fine sand. All other distances and sizes will be shrunk in the same proportion, that is, their actual size divided by the scale factor, 4.8x1010.
 Now apply your result: Question (A): How large will the sun be in your JOB 2 model? Diameter of the sun in your model is the actual diameter of the sun, divided by the scale factor. Solution: Diameter of the sun in your model is: _____________ / ___________ = _________

 In your JOB 2 model, the sun's diameter will be ________m   or    ______cm. or about the size of sphere _____ pictured on page 1.

 Question (B): How far will the Earth be from the Sun in your JOB 2 model? The distance in the JOB 2 model will be the actual Sun-Earth distance, divided by the scale factor. Solution: Sun-Earth distance in your model is: _____________ / ___________ = _________

 In your JOB 2 model, the distance from the Sun to the Earth will be _____m.

 Question (C): What will be the diameter of the solar system in your JOB 2 model? Diameter of the solar system in your model is the actual diameter of the solar system, divided by the scale factor. Solution: Diameter of the solar system in your model is:___________ / __________ = _______

 In your JOB 2 model, the diameter of the solar system will be ________meters, or ________times the length of a football field.

 Question (D): How far is it to Alpha Centauri in your JOB 2 model? Distance to Alpha Centauri in your model is the actual diatance to Alpha Centauri, divided by the scale factor. Solution: Distance to Alpha Centauri in your model is: _____________ / ___________ = _________

 In your JOB 2 model, the distance to Alpha Cenaturi, the nearest star (other than the sun), will be ________m   or    ______miles. Name a place that is about that far from your home town ______________________________________________________

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