# Can you see the forces at work?

We can't see forces, but we can perceive the impact they have on objects. Forces cause the Moon to orbit the Earth, items to fall to the ground, and birds to soar. Sir Isaac Newton was the inspiration for its name (1642-1727). He developed a theory of gravity that has been widely accepted since then.

## What are visible and invisible forces?

Science measures invisible (and visible) forces to make groundbreaking discoveries. Come along for the adventure as we strive to make these forces "visible" for you to comprehend, from ordinary background radiation to the more microscopic particle interactions. Science is full of unexpected results, and this activity helps students understand why scientists need to control variables in their experiments.

In addition to gravity and electromagnetism, other forces include the following:

Gravity - This is the force that causes objects with mass to attract each other. It acts over short distances and decreases as the square of the distance between objects. The greater the mass of an object, the stronger the pull of gravity it experiences. Gravity affects us all day every day, causing objects on earth to fall to the ground and planets to orbit around the sun. It also influences how galaxies cluster together by acting on distant objects with gravitational attraction.

Electromagnetic force - This is the force that acts across empty space and can only act between electrically charged particles. It does not interact with other types of matter and is responsible for the behavior of electrons and photons. Electromagnetic forces are important in physics because they play a role in almost everything that happens in the universe, from the explosion of a star to the transmission of electricity through copper wires to our DNA molecule. They are always present, but usually too small to see without help from technology.

## Why can we not see force?

We understand that we cannot perceive force, but we do understand that a push or pull is referred to as force. 1 Use force to modify the shape and size of an item. 2 A moving body is brought to a halt by force. When you apply a force to a flaming ball from the other direction, it comes to a halt. 3 Energy is transformed into force when one object pushes another.

So, we can assume that there is some type of invisible energy that is causing objects to attract or repel each other. This invisible energy is known as force.

It has been found that forces occur between all masses in nature. The study of these natural forces is called physics. Physics deals with matter and its interaction with energy and time. It is the science that explains how objects interact with each other and affect events around them. Physics classes include topics such as gravity, electromagnetism, optics, heat, atoms, molecules, nuclear physics, cosmic rays, and germs. Students are taught concepts like inertia, momentum, potential energy, work, force, acceleration, gravity, electromagnetism, light, and temperature during their physics classes.

In order for us to see forces, they must be applied directly to a mass. If an object is pulled toward something that is not visible, then we will not be able to feel its weight but rather its influence.

## What force cannot be seen but whose effect can be seen or felt?

Gravitational force is exerted on any item hurled into the air. That is why an item falls or comes down; the power of action cannot be seen, but it can be felt.

## Can we feel force?

It has been demonstrated that we lack a sense of what physicists refer to as force. In daily language, the phrase "force" refers to different processes. For example, if someone pushes on your shoulder, this is a force on your body. If you pull away from this person, then they are applying force against your body. Physicists use the word force in two ways when discussing gravity. The first is called passive gravity and it says that objects with mass can cause other objects or particles to fall toward them. An object's mass determines how much force it produces when it falls to the ground.

The second usage of the word force is called active gravity and it says that objects with mass can produce forces even when they are not falling. For example, if you jump up onto a table, you will exert a force on yourself and your body's mass will increase because of this action. This is an example of active gravity.

So, can we feel force? Yes, we can feel force! When someone pulls on our shoulder, we feel this force applied to our body. If we look at an object with mass, we can see this object producing force fields around itself. These are called gravitational forces and they act on all matter with mass, including us.

## What are the forces behind Grade 5?

A force is a push or pull on an object created by a collision with another object. Forces have an effect on things that are at rest or in motion. The three laws of motion of Isaac Newton describe how forces interact with objects to effect motion. Gravity, friction, and magnetism are all important forces.

Gravity is the strongest force in the universe. It acts on every particle in the universe and causes them to attract each other. This attraction between particles increases as objects get closer together; therefore, gravity gets stronger as objects get more massive. There is also a phenomenon called "gravity waves" which are ripples in space-time caused by changes in mass. These waves can be seen in gravitational lenses where multiple images of distant galaxies are warped into arcs by the energy from a massive galaxy cluster in the middle. Such clusters form when small groups of galaxies collide and connect their magnetic fields causing their dark matter to collapse into a single giant blob. Clusters this large contain enough mass to overwhelm their smaller neighbors and leave only one remaining galaxy in the center.

Friction is the force that causes objects to slow down when they touch something else. Friction occurs whenever two surfaces rub against each other; this usually happens when one surface has smooth bumps while the other surface has rough patches. The smoother the surfaces, the greater the force of friction. Softer materials, like rubber, tend to lose momentum easier when they hit something harder.

## What force attracts all matter?

Gravity is the attraction force that exists between all objects in nature. Gravity allows fruits and leaves to fall from trees, as well as planets to stay in orbit around the sun. Gravity may be seen most clearly in the behavior of massive things. When a mass is suspended from a fixed point above it, then gravity causes it to fall toward the earth.

In physics and astronomy, gravity's magnitude is expressed by the Greek letter "g". One newton (N) is the unit of force per mass; it is equivalent to the acceleration of gravity on earth, which is 9.8 N/kg. Therefore, one kilogram (kg) weighs about 1 N.

Gravity varies depending on distance but is always attractive. It is responsible for all terrestrial phenomena and can never be replaced by any other force. The study of gravity is called gravitational physics.

Gravity is a product of mass and acceleration due to gravity. The greater the mass, the stronger the pull of gravity on it. For example, if you weigh more than 150 pounds (70 kg), then your weight is pulling down hard on Earth's surface, causing it to collapse under your feet.

If there were no gravity, everything would fly off into space. No stars, no planets, no life as we know it. This shows how important gravity is for life as we know it.

##### Paula Mckinnon

Paula Mckinnon has been an educator for over 20 years. She loves to teach kids about science and how it relates to their everyday lives. Paula also volunteers as an advisor for college students who are interested in going into STEM (science, technology, engineering, and math) fields.

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