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Mass, which is the amount of stuff something is made of, is determined with the formula, force equals mass multiplied by acceleration. Use Newton's second law to determine the mass of an object with help from a math and science teacher in this free video on scientific equations.

Hi, I'm Steve Jones, and I'm going to tell you how to figure out mass. Well, it's not actually awfully easy to figure out, because mass is the one thing that is very difficult to measure. Normally, we measure mass by comparing it with another mass, so for example, if I have a set of scales and I have, that is, a balance I will put a mass on this side, and I'll put the object I want to measure the mass of on the other side and balance them. That's a standard device for measuring mass, but what is mass? Mass strictly, measured in kilograms or grams, is about the resistance to change in motion. If it has a big mass it resists change in motion, so if it has a big mass you need a big force to make it accelerate. If it has a small mass you need a small force to make it accelerate. Our problem is that on earth we get mixed up between mass and weight. Weight is a force. Weight is what gravity produces, but mass is there whether gravity is there or not. Mass is the amount of stuff something is made of kind of weight-wise, so we have to be very careful when we want to measure it. So, if we're measuring mass and figuring out mass we must use a balance of this kind. We must not use something like this that is a spring balance because that will measure force, not mass, so our mass might be on the end of it, but it's measuring actually the force and this is measured in Newtons, so be very careful to distinguish between the two, force and mass. So, how do I figure out mass? Well, I can measure it, or I can measure a force, measure the acceleration, and use the formula force is mass multiplied by acceleration which is Newton's 2nd Law. From Newton's 2nd Law we can calculate the mass by measuring the force and the acceleration. The force, we can measure using a measuring meter that measures force, and acceleration we can measure using the traditional methods, distance, time, and so on, okay? So, there we have a way of determining, figuring out mass.