The Unit of Force: The metric unit for force is the newton (N). This is named after Sir Isaac Newton. He was the scientist who discovered the force of gravity by sitting under an apple tree. On Earth, a 1.0 kg mass has a weight of 9.8 N.
Measuring Force: Meters that measure force normally contain a spring or elastic that stretches and compresses when force is applied to it. The most used force meter is called a spring scale (a.k.a. the Newton gauge). A spring scale the weight of an object in newtons. Spring scales can also determine how much force is required to move an object. A spring scale has a spring and a hook on the end. As more force is applied, the spring stretches farther. Spring scales can measure forces other than weight. For example, if you needed to know how much force it would take to slide an object across a table, you simply attach the spring scale to the object and pull at a consistent speed. By pulling the object parallel to the table, you are measuring the amount of friction between the object and the table.
Calculating the Force of Gravity (Weight): Scientists discovered that the mass and weight of an object are proportional. This means that an object with twice the mass has twice the weight. For example, a 1.0 kg mass on Earth, hanging from a spring scale, has a weight of 9.8 N. A 2.0 kg mass on Earth, hanging from a spring scale, would have a weight of 19.6 N. Therefore, by multiplying a mass by 9.8 N/kg, you will find its' weight on Earth. 9.8 N/kg, is classified as Earth's gravitational field strength. The metric unit for this is g.
The force of gravity (Fg) on any given mass (m) near the surface of Earth can be calculated by:
Force of Gravity = (mass of object) x (Earth's gravitational field strength)
or
Fg = mg
*where mass is in kilograms (kg) and g is 9.8 N/kg
For additional information about calculating force and gravity, watch the video below.
Calculating Force
The Unit of Force: The metric unit for force is the newton (N). This is named after Sir Isaac Newton. He was the scientist who discovered the force of gravity by sitting under an apple tree. On Earth, a 1.0 kg mass has a weight of 9.8 N.
Measuring Force: Meters that measure force normally contain a spring or elastic that stretches and compresses when force is applied to it. The most used force meter is called a spring scale (a.k.a. the Newton gauge). A spring scale the weight of an object in newtons. Spring scales can also determine how much force is required to move an object. A spring scale has a spring and a hook on the end. As more force is applied, the spring stretches farther. Spring scales can measure forces other than weight. For example, if you needed to know how much force it would take to slide an object across a table, you simply attach the spring scale to the object and pull at a consistent speed. By pulling the object parallel to the table, you are measuring the amount of friction between the object and the table.
Calculating the Force of Gravity (Weight): Scientists discovered that the mass and weight of an object are proportional. This means that an object with twice the mass has twice the weight. For example, a 1.0 kg mass on Earth, hanging from a spring scale, has a weight of 9.8 N. A 2.0 kg mass on Earth, hanging from a spring scale, would have a weight of 19.6 N. Therefore, by multiplying a mass by 9.8 N/kg, you will find its' weight on Earth. 9.8 N/kg, is classified as Earth's gravitational field strength. The metric unit for this is g.
The force of gravity (Fg) on any given mass (m) near the surface of Earth can be calculated by:
Force of Gravity = (mass of object) x (Earth's gravitational field strength)
or
Fg = mg
*where mass is in kilograms (kg) and g is 9.8 N/kg
For additional information about calculating force and gravity, watch the video below.
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