The weight of an item is the force of gravity acting on it and may be calculated as the mass multiplied by the acceleration of gravity, w = mg. Because weight is a force, the SI unit for it is the newton. Mass multiplied by volume equals density. So weight is mass times distance squared over time squared.

Weight can also be expressed in oz. Or lb. The ounce is 0.035 liter, while the pound contains **0.454 kilogram**. 1 kg = 2.2046 lb.

Weight scales measure mass; they are used to determine the weight of objects. Weight scales are useful in science labs as well as in hospitals to get a precise measurement of a patient's body weight. Commercial scale prices range from $10-$100 or more. Home weight scales are much less expensive and are available at grocery stores and home improvement stores.

There are two main types of **weight scales**: mechanical and electronic. Mechanical weight scales use a spring-loaded pointer connected to a dial or tablet display. As weights are placed on the scale, the gravitational force acts against **the biasing force** of the spring, causing the pointer to move. This movement is translated into numbers on the dial or screen. Electronic weight scales work similarly, but use sensors instead of springs to measure weight. These sensors can be pressure sensors, capacitance sensors, or magnetometers.

The formula for calculating an object's mass based on **its weight** is Mass equals weight divided by gravity's acceleration (M = W/G). Convert a weight measured in pounds to a weight measured in Newtons. Mass is measured in Newtons in the method for calculating mass based on weight.

Mass can also be expressed in kilograms or stones. 1 kilogram = 2.20462282131481 pounds, so 1 stone = 31.1 grams = 37.4 ounces.

Convert weights from pounds to grams and from pounds to stones. Use the conversion tables below to convert between weights in pounds and weights in grams or stones.

Note that the values in these tables are not exact; they're just good estimates based on standard weights and measures. So if you want to get an accurate reading, weigh yourself using certified scales and read the value under "Pounds" or "Ounces".

Also note that not all weights listed as pounds or stones are equal. For example, a pound weight will always be less than a kilo weight, and a half-pound weight is half as heavy as **a full pound weight**. When comparing weights across **different scales**, be sure to use weights that are recorded in the same unit of measurement.

Finally, keep in mind that the term "pound" refers to a unit of weight, not to a unit of volume.

"Mass is a unit of measurement for determining the weight of an object. The gram and kilogram are the most frequent mass units in the metric system of measurement. Other units such as the ounce, milligram, and microgram are also used but do not have as many applications as the gram or kilo." - Science Buddies

Grams are used to measure mass. As far back as we know, humans have been weighing objects using scales and measuring volumes of liquids using spoons and cups. Since **the early 20th century**, scientists have used grams to measure **small quantities** of substances that cannot be weighed individually. For example, a scientist might use grams to measure the concentration of a solution or the amount of radioactivity in an element.

Grams are based on the standard mass of 1/1000 of a kilogram, which is known as a decagram. A decagram is defined as **0.01 kg**. There are 10 grams in a decagram. One g is the weight of 1/10 of a kilogram, or 0.00001 kg.

Weight equals mass multiplied by **gravitational acceleration**. As a result, an object's weight is likewise changeable. The value of gravitational acceleration varies with a location's height. As a result, the weight varies according on a location's height. In general, weight increases as **altitude increases**.

As an example, assume that you go to the moon. There is no air so its gravity will be half of what it is on Earth. Therefore, the weight on the Moon is equal to **0.5 times the weight** on Earth. If someone weighs **180 pounds** on Earth but only 90 pounds on the Moon, then they are weightless on the Moon!

The reason this happens is because the force of gravity decreases as you get farther away from Earth's center. So, if you travel in space, you would need less and less force to stay at **a constant weight**.

This means that if you were to travel in space, you could actually lose weight! The closer you get to the Sun, the lighter you would feel because the solar wind blows away from it and into space, causing things to lose weight.

So, weight is just something that depends on where you are located on Earth or another planet. It can be fixed, like on Earth, or variable, like on Mars.