Physics

Problem

A tool kit weighs

98\,\text{N}

on Earth where

g=9.8\,\text{m/s}^2

. What are (i) its mass and (ii) its weight on Mars where

g=3.7\,\text{m/s}^2

? a)

10\,\text{kg};\;98\,\text{N}

10\,\text{kg};\;37\,\text{N}

9.8\,\text{kg};\;36.3\,\text{N}

10\,\text{kg};\;26.5\,\text{N}

Intuitive explanation

Mass is an intrinsic property that never changes, while weight is the gravitational force pulling on that mass—and it depends entirely on local gravity. Start by using Earth's weight and gravity to find the toolkit's mass, then use that same mass with Mars's weaker gravity to find its new weight. The key is recognizing that $g$ changes between planets, but the object itself stays the same.

Intuitive explanation

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