Explain why a reference points that are stationary are usually chosen to determine whether an object is in motion.

1 answer:

4 0

Answer: Stationary reference points are used to determine if a object is in motion because if the reference point is still,you will be able to see if the object is in motion. If you had a reference point that wasn't stationary, you wouldn't be able to tell if the object was in motion.

Explanation:

Stationary reference points are used to determine if a object is in motion because if the reference point is still,you will be able to see if the object is in motion. If you had a reference point that wasn't stationary, you wouldn't be able to tell if the object was in motion.

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This is note the complete question, the complete question is:

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Answer: 3.04 D

Explanation:

when an object is held 21 cm away from the instructor's eyes, the spectacle lens must produce 0.47m ( the near point) away.

An image of 0.47m from the eye will be ( 47 - 2 )

i.e 45 cm from the spectacle lens since the spectacle lens is 2cm away from the eye.

Also, the image distance will become negative

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Therefore;

image distance d₁ = - 45cm = - 0.45m

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