refraction

| The Speed of Light. The speed of light in a vacuum is 186,282 miles per second (299,792 kilometers per second), and in theory nothing can travel faster than light. In miles per hour, light speed is, well, a lot: about 670,616,629 mph.

Light has energy, energy is equivalent to mass, and mass exerts gravitational force. Thus, light creates gravity, i.e. the bending of space-time. Thus, in order for light to generate a gravitational field like that of the Earth, it would need to have the mass (energy) of the Earth.

You are right that according to Newton’s gravity, the force of gravity on particle that has 0 mass would be zero, and so gravity should not affect light.

Gravity bends light Light travels through spacetime, which can be warped and curved—so light should dip and curve in the presence of massive objects. This effect is known as gravitational lensing GLOSSARY gravitational lensingThe bending of light caused by gravity .

Also, under Einstein’s theory of general relativity, gravity can bend time. When anything that has mass sits on that piece of fabric, it causes a dimple or a bending of space-time. The bending of space-time causes objects to move on a curved path and that curvature of space is what we know as gravity.

Gravitational waves are ‘ripples’ in space-time caused by some of the most violent and energetic processes in the Universe. These cosmic ripples would travel at the speed of light, carrying with them information about their origins, as well as clues to the nature of gravity itself.

How much does light bend? When light travels from air into water, it slows down, causing it to change direction slightly. This change of direction is called refraction. When light enters a more dense substance (higher refractive index), it ‘bends’ more towards the normal line.

Yes, one bit of light can bounce off another bit of light, but not directly, and the effect is very rare. Light is made out of small quantum objects called photons.

Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely “no”: the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits.

Light is composed of photons, which have no mass, so therefore light has no mass and can’t weigh anything. Not so fast. Because photons have energy — and, as Einstein taught us, energy is equal to the mass of a body, multiplied by the speed of light squared.

It might be surprising to you to hear that gravity can affect light even though light has no mass. According to general relativity, gravity is actually caused by a curving of space and time. Since light travels in a straight line through straight spacetime, the curving of spacetime causes light to follow a curved path.

Light is not matter. Light is made up of “things” called photons, and these photons can possess some of the properties of matter. For example, they are always moving, and when they move, they can exert a (usually very small) force on an object (just like moving matter can).

Quantum theory tells us that both light and matter consists of tiny particles which have wavelike properties associated with them. Light is composed of particles called photons, and matter is composed of particles called electrons, protons, neutrons.

light, electromagnetic radiation that can be detected by the human eye. The speed of light in a vacuum is a fundamental physical constant, the currently accepted value of which is exactly 299,792,458 metres per second, or about 186,282 miles per second.

electromagnetic waves

There are 7 basic properties of light :

• Reflection of light.
• Refraction of light.
• Diffraction of light.
• Interference of light.
• Polarization of light.
• Dispersion of light.
• Scattering of light.

Light waves are just one type of electromagnetic wave. Other electromagnetic waves include the microwaves in your oven, radio waves, and X-rays. Light waves are regarded as a varying electric field (E) coupled with a varying magnetic field (B), at right angles to each other and to the direction of travel.

There are two basic types of light sources: Incandescence and Luminescence.

One way to categorize waves is on the basis of the direction of movement of the individual particles of the medium relative to the direction that the waves travel. Categorizing waves on this basis leads to three notable categories: transverse waves, longitudinal waves, and surface waves.

Light can be considered to be made of waves as well as particles. Sound is only a wave. It does not show particle nature. Light waves are electromagnetic waves while sound waves are mechanical waves.

The wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a vacuum at the same speed, the number of wave crests passing by a given point in one second depends on the wavelength.

Sound and light are similar in that both are forms of energy that travel in waves. They both have properties of wavelength, freqency and amplitude. Sound is a form of mechanical energy caused by vibrations of matter. Light is electromagnetic energy caused by interacting electric and magnetic fields.

Light and sound are both waves. The propagation, or distribution of sound, is actually very similar to light, just a whole lot slower. The waves of sound or light both reflect, refract, and attenuate depending on their environment.