Is wireless power/energy transmission a real possibility?
Wireless transmission is possible, but its efficiency degrades dramatically as more distance is added. Even your inductive electric toothbrush--which transmits electricity without wires across a few microns' distance--loses twice the electricity in transmission than a wire would. Certain advances have been made that allow reasonably efficient transfer of electricity across a few feet, and those devices will have some applications. However, anyone that is claiming they can transmit electricity across long distances (kilometers) at the same efficiency levels as wires has discovered a new truth to how the universe works that nobody else was able to discover, doesn't understand electro-magnetic physics or is lying.In most cases, it's the second or third options above. Let me explain the first option though. Electricity is not made of matter. It is a wave of energy that is co nstantly moving from the electron orbit of one atom to the electron orbit of another atom it is touching. Good conductors (like copper wires) transfer that energy very efficiently and very quickly (the speed of light). Air is the worst possibe conductor you could ask for. Atoms in the air are farther apart than atoms in a copper wire, so the electrical energy either doesn't move or it dissipates in random directions. Thus there is no good way to transfer electricity across air.Most attempts to do so involve changing the electricity into another form of energy (sound waves, microwaves, laser light beams, etc.) And anytime you convert energy from one form to another, you end up with efficiency losses.For those that mistakenly believe that space-based solar power is better than terrestrial power, answer me this: give one current application of microwave energy transmission that doesn't involve more than 50% efficiency losses over a distance greater than 1,000 feet.
How does refraction affect radio reception?
Radio propagation describes how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another.[1] Like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization and scattering.[2] Radio propagation is affected by the daily changes of water vapor in the troposphere and ionization in the upper atmosphere, due to the Sun. Understanding the effects of varying conditions on radio propagation has many practical applications, from choosing frequencies for international shortwave broadcasters, to designing reliable mobile telephone systems, to radio navigation, to operation of radar systems. Radio propagation is also affected by several other factors determined by its path from point to point. This path can be a direct line of sight path or an over-the-horizon path aided by refraction in the ionosphere. Factors influencing ionospheric radio signal propagation can include sporadic-E, spread-F, solar flares, geomagnetic storms, ionospheric layer tilts, and solar proton events. Radio waves at different frequencies propagate in different ways. The interaction of radio waves with the ionized regions of the atmosphere makes radio propagation more complex to predict and analyze than in free space. Ionospheric radio propagation has a strong connection to space weather. A sudden ionospheric disturbance or shortwave fadeout is observed when the x-rays associated with a solar flare ionize the ionospheric D-region. Enhanced ionization in that region increases the absorption of radio signals passing through it. During the strongest solar x-ray flares, complete absorption of virtually all ionospherically propagated radio signals in the sunlit hemisphere can occur. These solar flares can disrupt HF radio propagation and affect GPS accuracy. Predictions of the average propagation conditions were needed and made during the Second world war. A most detailed code developed by Karl Rawer was applied in the german Wehrmacht, and after the war by the French Navy. Since radio propagation is not fully predictable, such services as emergency locator transmitters, in-flight communication with ocean-crossing aircraft, and some television broadcasting have been moved to communications satellites. A satellite link, though expensive, can offer highly predictable and stable line of sight coverage of a given area.
Can someone please explain the difference between reflection and refraction?
a wave is just energy in motion. the boundary between two media is called an interface. when a wave encounters an interface, there are 3 possible things that can happen to its energy. (1) absorption (2) reflection (3) transmission. energy that is absorbed raises the temperature of the surrounding medium. energy that is not absorbed is reflected or transmitted. reflection means that the component velocity normal to the interface/surface changes sign. among the set of reflections, soft reflections preserve phase whereas hard reflections invert phase. refraction is what can happen to the energy that undergoes transmission. the underlying idea is that the wavespeed changes across the interface. so if the wavefront approaches the interface at an oblique angle (not normal or parallel) then the part of the wavefront that crosses the boundary first changes speed before the rest of the wavefront. whether the wavespeed increases or decreases, the net result is the same: the direction of the wave changes as a function of the ratio of the new and old wavespeeds. it is important to note that while the magnitude of the component wave velocity normal to the interface changes, its sign remains the same. so the difference lies in what happens with the sign of the component of the wave velocity normal to the interface. in the case of reflection it changes sign, in the case of refraction is remains the same.
What happens to plants if their leaves are covered with Vaseline?
anatomy of leaves suggests the presence of stomatal apparatus (typical cells facilitating gaseous exchange) on the bottom side. they facilitate the uptake of carbon dioxide (necessary for photosynthesis) and outflow of oxygen ( green pants are best source of oxygen in eco-biosystems). apart from the carbon dioxide and oxygen flow, water also moves out of plant body into environment - process termed as transpiration.though transpiration is water loss physiological activity, it has beneficial outcomes. transpiration exerts a upward pull on the water column in xylem vessels allowing more water uptake through root system in order to satisfy the water loss on hot days.vaseline is a mixture of waxes and mineral oils with property of locking moisture. when applied on leaf surfaces, the vaseline plugs stomata altering the gaseous exchange parameters. hence stopping the plant cellular metabolics in a step wise manner. death of local cells occurs followed by fatality of plant on long term basis.
What is evaporation? What are the factors affecting it?
The turning of any liquid into vapour is called Evaporation. The factors affecting the evaporation are:1. Temperature. As the temperature increases, the rate of evaporation also increases.2. Surface Area. As the Surface area increases, the rate of evaporation increases.3. Density. As the density increases, the rate of evaporation decreases.4. Wind Velocity. The velocity of the wind also affects the rate of evaporation. As the velocity of wind increases, the rate of evaporation increases.Reference and further readingsEvaporation - WikipediaWhat are the 6 factors that affect evaporation?
Does IR sensors see through water, or will it reflect off the surface of the water?
Whenever light energy hits a surface a number of things happen: - diffraction - scattering - transmission - reflection (specular and diffuse components) - absorption and some other phenomena. IR light is in the ~940 nm wavelength so depending on the index of refraction, surface distribution (i.e. Lambertian), etc. of the water (salt, spring, the temperature, etc.) the total light energy will be distributed across those many reactions. The IR emitters in your TV remote for example are surrounded by IR transparent plastic. If it is an LED the optical epoxy lens surrounding the die is IR transparent. The plastic in front of the emitter is transparent. The plastic in front of the IR detector in your TV is IR transparent. The plastic material (e.g. some polycarbonate) will dictate how much IR energy is lost and how it is distributed. Here is a cool trick. If you have a digital camera go into room and turn off the lights. Open up your TV remote and look at the IR emitter (probably an LED) through your digital camera when you press a button, like power. You will see it turn on and it will be a bluish-white color. The camera preforms some type fluorescence and you can see the IR light (note that IR light is not bluish-white in real life because humans cannot see wavelength that large). Anyways I hope this helps. My $0.02