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The mass of an object and it’s weight are different things. Here we’ll show you how mass, weight, and gravity are all related.

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Mass is the amount of matter in an object. Mass = The amount of matter in an object

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If we compare a small boy and a semi truck, the truck contains more matter than the boy, so the truck has a larger mass than the boy. Mass = The amount of matter in an object Smaller Mass Larger Mass

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Weight is the pull of gravity or force of gravity on an object. For an object on or near Earth, it is the force pulling the object toward Earth. Weight = Force of Gravity Weight

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If we compare objects on Earth, the more mass an object has, the greater the force of gravity on it, or the greater weight it has. Weight = Force of Gravity Weight

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In other words, less mass means less weight and more mass means more weight, so the truck has a greater weight than the boy. Weight = Force of Gravity Weight Less mass means less weight More mass means more weight

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Because weight is a force, it is measured in units of force called newtons, abbreviated with a capital N. Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Weight, or Force of Gravity, in Newtons

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Weight is equal to mass in kilograms Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Mass in kilograms

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Times something called the acceleration of gravity, measured in Newtons per Kilogram. Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Acceleration of Gravity in Newtons per Kilogram

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The value for the acceleration of gravity depends on the mass of the planet or moon the object is on or near. Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Acceleration of Gravity in Newtons per Kilogram Depends on the mass of the planet or moon the object is on or near

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On Earth, the Acceleration of Gravity is equal to 9.8 newtons per kilogram Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Acceleration of Gravity in Newtons per Kilogram Depends on the mass of the planet or moon the object is on or near On Earth, the Acceleration of Gravity = 9.8 N/kg

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We can use a capital W to stand for weight. Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Wmg

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A lower case m to stand for mass, Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Wmg

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And a lower case g to stand for acceleration of gravity. Weight (N) = Mass (kg) × Acceleration of Gravity (N/kg) Wmg

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Mass (kg) So now, we can just use these letters to give us an abbreviated form of this equation (click) Weight (N) = × Acceleration of Gravity (N/kg) = Wmg =

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The equation is W = m times g = × W m g

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Where W stands for the weight in newtons, = × W m g Weight in Newtons (N)

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M stands for the mass in kilograms, = × W m g Weight in Newtons (N) Mass in kilograms (kg)

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And g stands for the acceleration of gravity in newtons per kilogram. = × W m g Weight in Newtons (N) Mass in kilograms (kg) Acceleration of Gravity (N/kg)

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Here’s an example question. We’re given that a black bear has a mass of 190 kg. A black bear has a mass of 190 kg. What is its weight?

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And we’re asked for its weight. A black bear has a mass of 190 kg. What is its weight?

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It is important to know that for any questions involving mass and weight, if you are not told otherwise, assume that the object in question in on the surface of Earth. A black bear has a mass of 190 kg. What is its weight? Unless otherwise told, assume that the object in question is on Earth’s surface.

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We’re asked to calculate weight and we’re given mass, so we use the equation W = m times g, where W is the weight in newtons, m is the mass in kg, and g is the acceleration of gravity in N/kg. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg)

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The question tells us that the bear has a mass of 190 kg. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg)

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So we can substitute 190 kg in for mass A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W (N) 190 kg g (N/kg)

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It is known that the value for g on Earth is 9.8 newtons per kilogram. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg g (N/kg) “g” on Earth is 9.8 N/kg

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kg So we can substitute 9.8 newtons per kilogram in for “g” in this equation. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N “g” on Earth is 9.8 N/kg

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kg 190 times 9.8 is equal to 1862, A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N =

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kg we see that the unit kilograms is in the numerator and the denominator. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N = The unit kg is in the numerator and the denominator

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kg so they can be cancelled out, A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N = Can be cancelled out

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kg leaving us with only newtons as a unit. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N =

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kg So the unit for our answer is newtons. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N =

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kg So W is equal to 1862 newtons. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N =

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kg And we can state the final answer as the weight of a 190 kg bear is 1862 newtons. A black bear has a mass of 190 kg. What is its weight? = × W (N) m (kg) g (N/kg) = × W 190 kg 9.8 N W 1862 N = The weight of a 190 kg bear is 1862 N

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