Here's why:
* Mass is a fundamental property of matter that represents the amount of "stuff" in an object. It's a measure of its inertia, meaning its resistance to changes in motion.
* Forces can change an object's velocity (speed and direction), position, and shape, but they cannot change its mass.
Think about it:
* You can push a car to make it move faster (change velocity), but you can't make it heavier (change mass) just by pushing.
* You can bend a piece of metal (change shape), but you haven't changed its total amount of matter, so its mass remains the same.
Let me know if you have any other questions!
