Physics
Confusing Mass and Weight
Students treat mass in kilograms and weight in newtons as the same quantity.
Quick check
Why students make it
Everyday speech uses weight to mean how much matter something has. This makes kilograms feel like a force unit, even though they measure mass.
The rule done right
Mass is the amount of matter and stays the same when location changes. Weight is the gravitational force on that mass, so and its unit is the newton.
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