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A 5.0 kg wrench is taken to the Moon. What happens to it?

Its mass stays 5.0 kg; its weight drops, because the Moon's gravity is weaker.

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  1. Its mass and weight both drop
  2. Its mass stays the same, its weight drops ✔
  3. Its weight stays the same, its mass drops

Why: Mass is the amount of matter and does not change with location. Weight is the gravitational force on that mass, measured in newtons, so it shrinks where gravity is weaker.

Huh, didn't know that: On Earth a 1.00 kg object weighs about 9.80 N.

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References

Answer: Its mass stays the same, its weight drops. Mass is the amount of matter and does not change with location. Weight is the gravitational force on that mass, measured in newtons, so it shrinks where gravity is weaker.

  1. OpenStax University Physics Volume 1: 5.4 Mass and Weight openstax.org/books/university-physics-volume-1/pages/5-4-mass-and-weight
    the mass of the object is still 5.0 kg on the Moon
    Checked 2026-10-11.
  2. OpenStax University Physics Volume 1: 5.4 Mass and Weight openstax.org/books/university-physics-volume-1/pages/5-4-mass-and-weight
    weight of a 1.00-kg object on Earth is 9.80 N
    Checked 2026-10-11.

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