What are the two substances in fluorescent lights physics?

A fluorescent lamp consists of a glass tube filled with a mixture of argon and mercury vapour. Metal electrodes at each end are coated with an alkaline earth oxide that gives off electrons easily. When current flows through the gas between the electrodes, the gas is ionized and emits ultraviolet radiation.

How do fluorescent lights use quantum mechanics?

Fluorescent Lights Fluorescent bulbs contain electrodes that heat up and eject electrons. These electrons, in turn, bombard a tiny amount of mercury that is also inside the bulb. The collisions cause the mercury’s electrons to jump up to a higher quantum energy state.

What is fluorescent light science?

Fluorescence is the ability of certain chemicals to give off visible light after absorbing radiation which is not normally visible, such as ultraviolet light. This property has led to a variety of uses. Let’s shed some further light on this topic; consider the omnipresent “fluorescent” lights.

What type of energy is fluorescent?

In a fluorescent light bulb, electrical energy causes mercury vapor inside the light bulb to give off ultraviolet energy which is absorbed by the phosphor particles which coat the light bulb. The phosphor particles then glow, which gives off the visible light. This glow is known as ​fluorescence​.

How does a fluorescent light work physics?

Fluorescent lamps work by ionizing mercury vapor in a glass tube. This causes electrons in the gas to emit photons at UV frequencies. The UV light is converted into standard visible light using a phosphor coating on the inside of the tube.

How does a fluorescent light work a level physics?

Fluorescent tubes are filled with low pressure mercury, when an electric current is passed through, the electrons in mercury are excited and move to a high energy level, this high level state is unstable and so the electron moves back to its original state, but on doing so, it emits an electromagnetic wave with energy …

Why do fluorescent lights have waves?

An electric current in the gas excites mercury vapor, which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow.

How does a fluorescent tube produce photons?

A fluorescent lamp generates light from collisions in a hot gas (‘plasma’) of free accelerated electrons with atoms– typically mercury – in which electrons are bumped up to higher energy levels and then fall back while emitting at two UV emission lines (254 nm and 185 nm).

How do mercury atoms become excited in a fluorescent tube?

(i) As they pass through the fluorescent tube, they collide with the mercury atoms within it and this collision transfers energy to the atom. This energy transfer allows the atom’s orbiting electrons to move to a higher energy state thus exciting the atom.

How fluorescence is produced?

fluorescence, emission of electromagnetic radiation, usually visible light, caused by excitation of atoms in a material, which then reemit almost immediately (within about 10−8 seconds). The initial excitation is usually caused by absorption of energy from incident radiation or particles, such as X-rays or electrons.

What type of electromagnetic wave is used in fluorescent bulb?

Fluorescent – short-wave ultraviolet light that causes a phosphor coating on the inside of the lamp to glow. The fluorescent light spectrum has a high intensity at around 480 nm to about 570 nm. Fluorescent lights are mixed with other types of lights to produce a light that is closer to sunlight. 5.

What is fluorescence with example?

A fluorescence example would be if a 3s electron of a vaporized sodium atom is excited to the 3p state by absorption of a radiation at wavelength 589.6 and 589.0 nm. After 10-8 s, the electron returns to ground state and on its return it emits radiation of the two wavelengths in all directions.

Do fluorescent lights emit photons?

Single-Photon Generation and Detection When an atom emits from an excited level, the fluorescent light emitted is a one-photon wavepacket, as can be guessed merely from energy conservation.

What is the transformation of energy of fluorescent light?

In fluorescent light bulbs, the light is created by high-energy dislodged electrons that are produced when electric current is applied to the mercury gas; heat is created as a byproduct of these energetic electrons. About 85% of the energy used by a fluorescent bulb is converted to light.

Why are fluorescent lights more efficient?

Fluorescent lamps are more efficient than incandescent light bulbs of an equivalent brightness. This is because a greater proportion of the power used is converted to usable light and a smaller proportion is converted to heat, allowing fluorescent lamps to run cooler.

Why does a fluorescent tube not generate heat?

Tube lights dissipate heat which means that the power that they use to light up, is consumed and as the first law of thermodynamics goes, energy can neither be created nor be destroyed but only transformed into another form.

How does glow in the dark work?

When you have something like a toy that glows in the dark, it can glow because it contains materials called phosphors. Phosphors can radiate light after they have gotten energy from the sun or another source of bright light. The phosphors soak up the energy from the light, and then they radiate this energy as light.

Why is Mercury Vapour at low pressure in a fluorescent tube?

The initial high voltage burst is necessary to produce electrons with enough kinetic eergy to ionise the mercury atoms – the atoms in the gas need to be sparse enough (low pressure) so that KE can be built up to a level that will allow ionisation of the mercury atoms.

What do fluorescent light bulbs contain?

The tube contains a small bit of mercury and an inert gas, typically argon, kept under very low pressure. The tube also contains a phosphor powder, coated along the inside of the glass. The tube has two electrodes, one at each end, which are wired to an electrical circuit.

Is there mercury in fluorescent tubes?

Fluorescent bulbs are an energy-saving alternative to incandescent lights, but did you know that all fluorescent lighting including lamps, bulbs, tubes and compact fluorescent lamps (CFLs) contain mercury and may not be thrown in the landfill?

When high energy radiation falls on a fluorescent material it produces flashes of light is called as?

Fluorescence is simply defined as the absorption of electromagnetic radiation at one wavelength and its reemission at another, lower energy wavelength. Thus any type of fluorescence depends on the presence of external sources of light.

Why does the tube light blink?

Lamp blinks: This is usually because of a poor connection where the tube fits into its sockets at each end. Take the tube out and clean the pins at each end with fine steel wool. Brush dust out of sockets, then reseat firmly.

Why do fluorescent lights flicker when turned off?

When a CFL flickers, the cause is usually in the light switch, which is either a dimmer or a switch with an illuminate rocker. Illuminated switches pass a small amount of current even when they’re turned to the “off” position, which is enough to charge the capacitor in the CFL and cause a momentary illumination.

Why do new fluorescent lights flicker?

More noticeable fluorescent lamp flickering occurs at the end of the fluorescent lamp’s life and is a sign that the lamp (bulb) is ready for replacement. However there are other sources of abnormal flickering fluorescent light fixtures that mean repairs are needed.

What gas is in fluorescent lights?

The Bad: Fluorescent tubes & CFL bulbs contain a small amount of mercury gas (about 4 mg) – which is toxic to our nervous system, lungs and kidneys. So long as bulbs stay intact, the mercury gas is no threat. This means bulbs should be handled properly to avoid breakage.

Do NOT follow this link or you will be banned from the site!