Motion Glossary and Terms

                         Motion Glossary and Terms

 Acceleration - Acceleration is the measurement of the change in an object's velocity. It is equal to the change in velocity over the change in time. Acceleration is a vector. 

Collision - A collision in physics occurs when any two objects bump into each other. 

Displacement - In physics, displacement refers to an object's overall change in position. It is a vector quantity. 

Energy - Energy is the ability to do work. The standard unit of measure for energy is the joule. 

First law of motion - The first law of motion states that any object in motion will continue to move in the same direction and speed unless external forces act on it. 

Force - Force is the measurement of a push or pull on an object. Force is a vector measured in newtons. 

Friction - Friction is the resistance of motion when one object rubs against another. It is a force and is measured in newtons. 

Gravity - Gravity is a force caused when the mass of physical bodies attract each other. On Earth gravity pulls at objects with an acceleration of 9.8 m/s². 

Impulse - An impulse is a change in momentum. 

Joule - The joule is the standard unit of measure for energy and work. 

Kinetic energy - Kinetic energy is the energy an object has due to its motion. It is a scalar quantity calculated using the formula KE = ½ * m * v², where m = mass and v = velocity. 

Mass - Mass is a measurement of how much matter is in an object. It is usually measured in kilograms. 

Momentum - Momentum is a measurement of mass in motion. Momentum is equal to the mass times the velocity of an object. It is a vector measured in newton-seconds. 

Newton - The newton is the standard unit of measure for force. 

Pascal - The pascal is the standard unit of measure for pressure. 

Potential energy - Potential energy is the energy stored by an object due to its state or position. It is measured in joules. 

Power - Power is a measurement of the rate at which energy is used. Power is calculated by dividing work over time. The standard unit for power is the watt. 

Pressure - Pressure is the force over a given area. Pressure is measured in pascals. 

Scalar - A scalar is a measurement that only measures the magnitude. Unlike a vector, a scalar does not have direction. 

Second law of motion - The second law of motion states that the greater the mass of an object, the more force it will take to accelerate the object. 

Simple machine - A simple machine is a basic mechanical device for applying a force and doing work. Some examples of simple machines include the lever, pulley, inclined plane, wedge, and screw.

Speed - Speed is the measurement of how fast on object moves relative to a reference point. It is a scalar quantity measured by distance over time. 

Third law of motion - The third law of motion states that for every action there is an equal and opposite reaction. 

Vector - A vector is a quantity that has both a magnitude and a direction. 

Velocity - Velocity is the rate of change in an object's position. Velocity is a vector quantity. The magnitude of velocity is the object's speed. 

Watt - The watt is the standard unit of measure for power. 

Weight - Weight is the force of gravity on an object. In physics, weight is measured in newtons. 

Work - Work occurs in physics when a force acts on an object to move it some distance. Work is equal to the force times the distance and is measured in joules. 

What is Radiant Energy?

What is Radiant Energy?

What's the first thing you think of when you think of the sun; warmth, light, sunburns, blue skies, growing plants? The energy from the sun is an important factor for life on earth. The heat and light we associate with the sun are forms of radiant energy. Energy is the ability to do work, and radiation is energy that travels in waves. There are other forms of radiant energy besides heat and light. All the different forms of radiant energy make up the -electromagnetic spectrum.

What is the Electromagnetic Spectrum?

Have you observed a rainbow after it rains? All those colors of light are a small part of the electromagnetic spectrum and the only part we can see. We see the light from the sun, but don't necessarily see the heat. Heat is known as infrared light. Some of the other forms of radiant energy you may know are ultraviolet light, x-rays, gamma rays, microwaves and radio waves. All these forms of radiant energy travel in waves at the same speed but each forms' waves are different in size. Radio waves are very large, low energy waves traveling through the air (though we can't see them) in comparison to x-rays that are small, high energy waves.

A rainbow is radiant energy we can see

How is it used?

Sir William Crookes discovered the electromagnetic spectrum in 1885. That's over 130 years ago! Scientists are still studying and learning about radiant energy, how it works and how we can use it. Radiant energy is an important part of our world. Telecommunications like wireless networks, remote controls, heating, lighting, and branches of the medical field such as laser surgery and radiation therapy are just a few examples of our current technological uses of radiant energy.