Power of attraction, armed forces, gravitational force, and lifting power. Powerhouse, force field, fuel, and powerful action. Atomic power, power of healing, muscular power, and mental power. Power lifter, expression of power, power food, and power plant. Half-time workforce, wind power, and bounce power… We encounter the notions of force and power time and again in everyday life – in their literal as well as figurative senses. These terms are omnipresent, yet remain abstract.

Force and power are terms derived from physics. Force refers to something that can cause acceleration or deformation of a body. Force is the power needed to get work done. In that process, energy is consumed.

The Four Forces

Force appears in four fundamental forms, also known as the basic forces of physics:

1. Gravitational force
The first of these is, of course, gravitational force (gravity). It not only acts through the Earth onto us, but also in the opposite direction. Even if the impacts may not be tangible, every mass in the universe attracts every other mass to it. Gravitational force is always attractive and is dependent not only on its mass, but also on its distance from other masses. Its strength is inversely proportional to the square of the distance between them. This means that gravitational force has an infinite range.
Exchange particles, “gravitons,” have a relative strength of 10-38 and a range [m] of ∞.

2. Electromagnetic force
The next force familiar to us from everyday life is electromagnetic force. This occurs wherever electrically charged particles interact. Some example are electricity, radio waves, and sunlight. Electromagnetic force is caused by electrical charge and can attract (in the case of opposing charges) or repel (where charges share the same polarity). Their range is infinite and, like gravity, decreases at the square root of distance between charges.
Exchange particles, “photons,” have a relative strength of 10-2 and a range [m] of ∞.

3. Weak force
This type of force is very closely linked to radioactivity and causes our sun to produce light. Weak force is what enables elementary particles to transform themselves into one another. For example, an electron can turn into a neutrino, and a quark can transform itself into a different quark – a process known as beta decay, where a neutron turns into a proton. Weak force occurs only among subatomic particles, and their range extends to only one thousandth of the diameter of a proton. Although weak and strong forces are essential to life, people are generally unaware of their existence.
Exchange particles – W+, W, and Z0 – have a relative strength of 10-3 and a range [m] of 10-18.

4. Strong force
This is the force that holds atomic nuclei together. Quarks in each nucleus communicate with one another by exchanging gluons. The further they move apart, the greater the strong force becomes, and this holds these particles together. Strong force is the most powerful of the four natural forces, but it has only the range of one atomic diameter.
Exchange particles, “gluons,” have a relative strength of 1 and a range [m] of 2.5 x 10-15

Life on Earth is, therefore, determined by these four forces. Modern physics assumes that, before the Big Bang, only one elemental force commanded everything that occurred. During the expansion that accompanied the Big Bang, the one force separated into four. In actual fact, these four forces are four presenting forms of that one elemental force. If the Big Bang theory is correct, it follows that we should be able to describe the four forces within a shared theoretical framework, known as the “theory of everything” (ToE).

How Are Forces Applied?

A tension link for measuring force in production

In practice, we are almost entirely unaware of strong and weak forces. In contrast, we are very aware of the actions of the forces of gravity and electromagnetism – when lifting loads, measuring weights, or securing bridges; whenever stresses arise in systems; and whenever we are simply in motion.

These forces can be measured on cranes, lifting gear, and mobile machinery. They can be measured in geotechnology, stage mechanics, mechanical engineering, medical technology, and robotics. A force sensor can make a decisive contribution to saving you time as a customer because it can safeguard your investment by protecting against the possibility of mechanical failure.

So, talk to us if you are wondering which force sensor is best suited for your application; which components provide measurement accuracy, safety, and cost-effectiveness; or if you wish to find out how to save space, weight, and, therefore, cost. With almost 20 years of expertise in force measurement, the WIKA Group has the right answers to meet your challenges.

You may also be interested in these articles about force:
Load Pins: What They Are and How to Use Them
Bending Beams and Shear Beams: Indispensable in Weighing Technology
The Strain Sensor in Practical Application