How can electromagnetic waves travel through space

All electromagnetic waves:. Some types of electromagnetic waves, like radio waves, microwaves, infrared waves, visible light and ultraviolet waves, can be reflected and refracted. Refraction is caused by differences in the velocity of waves travelling through different substances.

Electromagnetic waves form a continuous spectrum of waves. This includes:. When you listen to the radio, watch TV, or cook dinner in a microwave oven, you are using electromagnetic waves. Radio waves, television waves, and microwaves are all types of electromagnetic waves. They only differ from each other in wavelength.

Wavelength is the distance between one wave crest to the next. Waves in the electromagnetic spectrum vary in size from very long radio waves the size of buildings, to very short gamma-rays smaller than the size of the nucleus of an atom. Yet their size can be related to their energy. The smaller the wavelength the higher the energy. For example, a brick wall blocks visible light wave lengths. Smaller, more energetic, x-rays can pass through brick walls, but themselves are blocked by denser material such as lead.

While it can be said waves are "blocked" by certain materials, the correct understanding is that wave lengths of energy are "absorbed" by objects, or not. That is, wave length energy can be absorbed by certain material. We use this knowledge in weather satellites as the atmosphere also absorbs some wave lengths while allowing others to pass through. This is a scientific convention that allows the convenient use of units that have numbers that are neither too large nor too small.

The number of crests that pass a given point within one second is described as the frequency of the wave. One wave—or cycle—per second is called a Hertz Hz , after Heinrich Hertz who established the existence of radio waves.

A wave with two cycles that pass a point in one second has a frequency of 2 Hz. Electromagnetic waves have crests and troughs similar to those of ocean waves. The distance between crests is the wavelength. The shortest wavelengths are just fractions of the size of an atom, while the longest wavelengths scientists currently study can be larger than the diameter of our planet!

An electromagnetic wave can also be described in terms of its energy—in units of measure called electron volts eV. An electron volt is the amount of kinetic energy needed to move an electron through one volt potential. Moving along the spectrum from long to short wavelengths, energy increases as the wavelength shortens.

Consider a jump rope with its ends being pulled up and down. More energy is needed to make the rope have more waves. Top of Page Next: Wave Behaviors. Anatomy of an Electromagnetic Wave. Retrieved [insert date - e. Science Mission Directorate.

National Aeronautics and Space Administration. Anatomy of an Electromagnetic Wave Energy, a measure of the ability to do work, comes in many forms and can transform from one type to another. Classical waves transfer energy without transporting matter through the medium.

Waves in a pond do not carry the water molecules from place to place; rather the wave's energy travels through the water, leaving the water molecules in place, much like a bug bobbing on top of ripples in water.

When a balloon is rubbed against a head of hair, astatic electric charge is created causing their individual hairs to repel one another. Credit: Ginger Butcher. Electromagnetic Spectrum Series Series Homepage. Infrared Waves. Reflected Near-Infrared. Visible Light.