Force is a push or pull measured in newtons, named after the scientist Isaac Newton. Force can alter the shape of an object. It can also change the direction of motion of an object, or increase or decrease its speed.
It is possible to measure force using a device called a force meter. The front of the force meter features markings that indicate the number of newtons. Running through the center of the device is a measuring section on a spring with a metal hook on the end.
Hanging an object on the hook of a force meter results in the spring stretching due to the pull of the force. If the object exerts a large amount of force, then the spring stretches a long distance. An experimenter can read the measurement of force from the markings on the meter.
There are effectively two types of forces. Contact forces result in a direct physical interaction, such as air resistance, friction or tension. Other forces act at a distance in a non-physical interaction, such as gravity or magnetic forces.Learn more about Motion & Mechanics