Mass vs. Weight Leonard M. Fischer Horace Mann Middle School Center for Applied Technology 8950 NW 2nd Avenue El Portal, FL 33150

Mass vs. Weight Question: What weighs more, a pound of feathers or a pound of bricks? Answer: They both weigh the same. A pound is a pound.

Mass vs. Weight In everyday usage, the mass of an object is often referred to as its weight. This is WRONG. Mass is NOT the same as weight. In fact, what we usually refer to as the weight of an object, is really actually its mass. So what is the difference?

What is Mass? As we have already discussed, all Matter is made up of smaller pieces (for example, atoms and molecules). Mass is simply a measure of how much “stuff “ there is in an object. Remember our boxes from the density review? Let’s look at them again.

Mass vs. Weight Which box has more matter in it? Box A Box B Which box has more matter in it? Accordingly, which box has more mass?

Measuring Mass We measure mass using a Triple Beam Balance. The unit we use to measure mass is the gram (g).

Mass is Constant No matter where you go in the Universe, the amount of Mass in an object doesn’t change. If I were to go to the moon, would I suddenly get smaller? Would I magically end up with less matter in me? Of course not. My mass remains the same!

What is Weight Weight, on the other hand, is a measure of the pull of gravity on an object. The weight of an object depends on the amount of mass and the force of gravity. Mass Gravity

What is Weight For instance, you all know that on Earth an object with more mass has more weight than an object with less mass. Mass Gravity

What is Weight What if we go to the moon? We know gravity is less on the moon than it is on Earth. Mass Gravity

What is Weight Since the gravity on the moon is less, it pulls down on the mass with less force. Therefore, an object weighs less on the moon, even though its mass is the same. Mass Gravity

How do we Measure Weight? We measure weight using a scale. Since weight is really a measure of the force of gravity, the unit we use is the Newton (N).

Weight vs. Mass The writer of the Superman Comics was aware of this. Superman came from a much more massive planet than Earth. As a result, his muscles were used to a stronger gravitational pull. So, when he came to Earth, he was super strong.

Weight vs. Mass Any Questions???