Once upon a time in the West
In physics, the term dielectric strength has the following meanings:
- for a pure electrically insulating material, the maximum electric field that the material can withstand under ideal conditions without undergoing electrical breakdown and becoming electrically conductive (i.e. without failure of its insulating properties).
- For a specific piece of dielectric material and location of electrodes, the minimum applied electric field (i.e. the applied voltage divided by electrode separation distance) that results in breakdown. This is the concept of breakdown voltage.
The theoretical dielectric strength of a material is an intrinsic property of the bulk material, and is independent of the configuration of the material or the electrodes with which the field is applied. This "intrinsic dielectric strength" corresponds to what would be measured using pure materials under ideal laboratory conditions. At breakdown, the electric field frees bound electrons. If the applied electric field is sufficiently high, free electrons from background radiation may be accelerated to velocities that can liberate additional electrons by collisions with neutral atoms or molecules, in a process known as avalanche breakdown. Breakdown occurs quite abruptly (typically in nanoseconds), resulting in the formation of an electrically conductive path and a disruptive discharge through the material. In a solid material, a breakdown event severely degrades, or even destroys, its insulating capability.
In electromagnetism, a dielectric (or dielectric medium) is an electrical insulator that can be polarised by an applied electric field. When a dielectric material is placed in an electric field, electric charges do not flow through the material as they do in an electrical conductor, because
they have no loosely bound, or free, electrons that may drift through the material,
but instead they shift, only slightly, from their average equilibrium positions, causing dielectric polarisation.
Because of dielectric polarisation, positive charges are displaced in the direction of the field and negative charges shift in the direction opposite to the field.
This creates an internal electric field that reduces the overall field within the dielectric itself. If a dielectric is composed of weakly bonded molecules, those molecules not only become polarised, but also reorient so that their symmetry axes align to the field.[1]
The study of dielectric properties concerns storage and dissipation of electric and magnetic energy in materials.[2][3][4] Dielectrics are important for explaining various phenomena in electronics, optics, solid-state physics and cell biophysics.[5][6]
Voltage, also known as (electrical) potential difference, electric pressure, or electric tension, is the difference in electric potential between two points.[1][2] In a static electric field, it corresponds to the work needed per unit of charge to move a positive test charge from the first point to the second point. In the International System of Units (SI), the derived unit for voltage is the volt (V).[3][4][5]
The voltage between points can be caused by the build-up of electric charge (e.g., a capacitor), and from an electromotive force (e.g., electromagnetic induction in a generator).[6][7] On a macroscopic scale, a potential difference can be caused by electrochemical processes (e.g., cells and batteries), the pressure-induced piezoelectric effect, and the thermoelectric effect. Since it is the difference in electric potential, it is a physical scalar quantity.[8]
What is it:?
Flows freely within any channel
Spits on occasion
can be contained
is a container
flows along the path of least resistance
seeks itself always
always seeks balance
is capable of determining resistance at any level
is capable of resisting at all levels
Is conducted in duct like tubes hollowed by regular geometry
moves itself
is self moving
organizes itself
is self organizing
can be stored
is self storing
is not generally visible
is all forms of light including heat
is present and detectable at all levels everywhere
is generally not sensed
is sense able at any level
- Two large, heavy-duty containers or barrels: Use strong, non-corrosive material like plastic or ceramic. The larger the containers, the more accurate and longer-running your clock will be. The inner barrel should be slightly smaller than the outer one.
- A smaller, clear vessel: This will be your clock's measuring vessel. A large, clear plastic or glass cylinder works best.
- A float and a dowel: The float should be buoyant and non-porous, such as a cork. The dowel should be lightweight and straight, like a garden stake.
- Plumbing hardware:
- One 1/4-inch ball valve
- Flexible plastic tubing
- Hose connectors, fittings, and plumber's putty
- Frame and support: Use sturdy, non-rusting materials like treated wood or copper pipe to build a frame that holds the components steady and vertical.
- Tools: Drill, fine-tipped permanent marker, stopwatch, and measuring tape.
- Prepare the outer barrel: Use a drill bit slightly larger than your tubing to drill a hole roughly 2 inches from the top of the outer barrel. This will act as an overflow drain.
- Prepare the inner barrel: Drill a hole near the bottom of the inner barrel, about 1/2 inch from the base. Seal the tubing into this hole with a hose connector and plumber's putty. This will be the water outlet that supplies the clock.
- Assemble the reservoir: Place the inner barrel inside the outer barrel. Run the tubing from the inner barrel's water outlet to the top of your clear measuring vessel. Mount the entire assembly on a sturdy, level frame.
- Prepare the vessel: Mark a "0 hours" line near the bottom of your clear measuring vessel with a fine-tipped marker.
- Create the float stick: Press one end of the lightweight dowel into the cork to create a float stick. The cork should be at the bottom.
- Create the guide: Secure a wooden stake or similar guide next to the measuring vessel. Attach two eyelet screws to the guide so the dowel can pass through them. The eyelets will keep the float stick upright and prevent it from wobbling.
- Assemble: Place the float stick inside the clear measuring vessel, guided by the eyelet screws.
- Adjust the flow: Connect your water source to the overflow hole in the outer barrel. Open the water supply slowly, allowing the outer barrel to fill. Excess water will exit through the overflow hole, creating a constant water level and pressure in the outer barrel. This consistent pressure will ensure a steady drip from the inner barrel's outlet.
- Fine-tune the drip rate: Use the ball valve on the tubing from the inner barrel to adjust the water flow into the measuring vessel. Aim for a slow, steady, and constant drip.
- Time the first hour: Fill the reservoir and start a stopwatch when you open the valve to begin the drip into the measuring vessel. After one hour, mark the water level on the measuring vessel with your marker.
- Calibrate the clock: After marking the first hour, continue marking the water level at one-hour intervals for a full 12 hours. The water marks will likely not be evenly spaced due to imperfections, so marking each individual hour is necessary for an accurate clock.
- Operate the clepsydra: To begin a new 12-hour cycle, simply fill the reservoir to the overflow level. The float stick will rise in the measuring vessel as it fills, and you can read the time on the side of the vessel.
- Replenish the water: To keep the clepsydra running continuously, you can use a small, low-powered electric pump to supply the reservoir from a water tank. Ensure the flow rate is balanced so the overflow drain always runs.
- Perform maintenance: Check for leaks periodically. Over time, the hole may change due to mineral deposits or wear, affecting accuracy. Keep the water clean to prevent blockages.
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