虽然在日常语言中经常互换使用，但质量和重量具有不同的科学含义：
质量
物体中的物质数量
以公斤（kg）或克（g）测量
无论位置如何都保持不变
使用天平进行测量
fundamental property of matter
重量
the force exerted on an object by gravity
measured in newtons (n) in si units
varies with gravitational pull
measured using a scale
depends on mass and gravitational acceleration
in common usage, when we say "weight" in kilograms or grams, we're actually referring to mass. this converter handles mass conversions between kilograms and grams.