Why do radio waves pass through objects?
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Ok, so some people should not be posting answers here.\n\nRadio waves do not pass through all objects.  It depends on two things, the dielectric constant of the object and thus the frequency of the radio wave.\n\nFor example, if you have a conductor (copper, or aluminum or iron) it will reflect the radio waves.  The waves will not pass through the object.\n\nFor most objects that are not conductors, when you pass from free space (air) to a solid like concrete, a portion of the radio wave will reflect off the surface (a small portion), some of the energy of the wave will be absorbed by the object, but the rest of the wave will pass through. \n\nDepending on the thickness of the material and the frequency of the signal, and the dielectric constant of the material, sometimes radio waves will not pass through the object.  As the signal travels through the material, it will continuously lose active power (heat) and reactive power (stored energy like in a capacitor).\n\nIf you were to compare the signal strength before it hits the wall, and the signal strength after it leaves the other side of the wall, some energy would have been lost.
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so that energy can be transmitted through a medium effectively without having the particles move from one end to the other. they simply need to pass the energy on to the next particle and so on
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Radio propagation\nRadio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another.\n\nIn free space, all electromagnetic waves (radio, X-rays, visual, etc) obey the inverse-square law which states that an electromagnetic wave's strength is proportional to 1/(x2), where x is the distance from the source. Doubling the distance from a transmitter means the strength is reduced to a quarter, and so on.\n\nRadio propagation on Earth is not only affected by the inverse-square model, but by a number of 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 (see also radio horizon) path aided by reflection from the ionosphere. A variety of phenomena make radio propagation more complex.\n\nSince radio propagation is somewhat unpredictable, such services as emergency locator transmitters, in-flight communication with ocean-crossing aircraft, and some television broadcasting have been moved to satellite transmitters. A satellite link, though expensive, can offer highly predictable and stable coverage of a given area.\n\nA sudden ionospheric disturbance is often the result of large solar flares directed at earth. These solar flares can disrupt HF radio propagation.\n\nPropagation modes\nRadio waves at different frequencies propagate in different ways.\n\n\nThe Antenna\nThe beginning and end of a communication circuit is the antenna. The antenna will provide gain and directivity on both transmit and receive. The take off angle of the antenna is based on the type of antenna, the height of the antenna above ground, and the type of ground below and in front of the antenna. The take off angle will determine the angle of attack on the ionosphere, which will effect if and where the signal will be reflected by the ionosphere.\n\nGround wave Propagation\nGround waves are radio waves that follow the curvature of the earth. Ground waves progress along the surface of the earth and must be vertically polarized to prevent short circuiting the electric field through the conductivity of the ground. Since the ground is not a perfect electrical conductor, ground waves are attenuated as they follow the earth’s surface. At low frequencies, ground losses are low and become lower at lower frequencies. The VLF and LF frequencies are mostly used for military communications, especially with ships and submarines.\n\nEarly commercial and professional radio services relied exclusively on long wave, low frequencies and ground-wave propagation. To prevent interference with these services, amateur and experimental transmitters were restricted to the higher (HF) frequencies, felt to be useless since their ground-wave range was limited. Upon discovery of the other propagation modes possible at medium wave and short wave frequencies, the advantages of HF for commercial and military purposes became apparent. Amateur experimentation was then confined only to authorized frequencies in the range.\n\nLine-of-Sight Propagation\nGround plane reflection effects are an important factor in VHF line of sight propagation. The interference between the direct beam line-of-sight and the ground reflected beam often leads to an effective inverse-fourth-power law for ground-plane limited radiation.\n\nSkywave Propagation\nSkywave propagation is any of the modes that rely on reflection of radio waves from the ionosphere, which is made up of one or more ionized layers in the upper atmosphere. These layers are directly affected by the sun, and its varying activity (sunspot cycle) determines the utility of these modes. Forecasting of skywave modes is of considerable interest to amateur radio operators and commercial marine and aircraft communications, and also to shortwave broadcasters.\n\nTropospheric Scattering\nAt VHF and higher frequencies, the atmosphere at a height of around 6 miles (10 kilometres) can scatter some of the norm
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As others have answered, it's because the signal is passed from one "cell", or transmitting tower to another as you move.\n\nUp until the mid or late 80's, there were still mobile phones which were not cell phones.  These were basically just specialized radios, and had limited range.  They were expensive and limited to people like doctors and the wealthy.  I'm not sure when they finally phased them out, or even if they are still available somewhere, but as cell phones became more & more common, and the coverage got better, there was just no need for the old style mobile phones, and the two terms became synonymous.
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Light waves are in the visual spectrum and so they bounce off of solid objects.. Radio waves like X rays are in a non visual spectrum and penetrate.
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The main concept to understand is that of a carrier wave.  The radio wave is that.  A radio wave is electro-magnetic radiation, which, unlike other waves, is not a vibration within a medium, like sound waves for example, which are the propagation of alternating high and low pressure within the air, or other fluid media.  Electro-magnetic waves are a self propagating electro-magnetic effect which can travel even in a vacuum.  Electro-magnetic radiation is a pulsing stream of energy where the pulses are at a constant frequency.  What we perceive as different phenomenon are in fact the same electromagnetic radiation but at different frequencies.  Microwaves, Radio, Ultra-violet, Visible Light, and Infra-red, are all electro-magnetic radiation moving down the scale from high to low frequency.\n\nThe radio transmitter sends out radio waves at a specific frequency or band of frequencies.  The aerial of the receiver develops tiny electric currents in it as the radio wave flows past it.  These are pulsing currents at the same frequency as the radio wave, but these pulses are not in themselves the content of speech or music.  This content, or signal, is carried in the wave, hence the concept of the carrier wave.\n\nIt is easier to understand Amplitude Modulation or AM radio so I will restrict myself to that.  If you imagine a radio wave as a very long string with the pulses like beads on it, all spaced at precise intervals, then imagine that the beads slowly getter bigger and smaller along its length.  Each bead is a packet of energy in the wave and all occur at the same frequency, but where the beads get bigger there is more energy in the packet.  It only takes a little more imagination now to see how the pattern of a sound wave can be represented by the bulging out of the beads, and their getting smaller.  This is called the amplitude.\n\nLooking at it in practical terms, at the transmitter end sound is converted in the microphone into a corresponding pattern of changes in the current flowing through the microphone.  That is your signal.  That signal which is at a low electrical power, is used to create the same pattern but in a circuit of much higher electrical power - that is what an amplifier does.  The device used to transfer the pattern is called a transistor, which uses the low powered circuit to control the flow in the high powered circuit.\n\nThe amplified signal is fed to the transmitter aerial, so now that pattern of electrical energy, identical to the pattern of the sound picked up by the microphone, comes out of the aerial as radio waves, with the pattern held in the varying amplitude of the radio wave.\n\nNow comes a trick to follow.  If there are thousands of transmitters all radiating radio waves all over the place, how come your radio only picks up the one signal.  This is where the tuner comes in.  The principle of radio tuning depends on the opposite properties of coils and capacitors.  I don't know if you know what these are, but it doesn't matter if you don't.  Both of these devices have a special kind of resistance to electricity known as impedance.  Impedance only operates where the current is varying.  The voltages and currents in our radio Ariel will be varying at exactly the same frequency as each radio wave it is exposed to, so if we pass that current through either a coil or a capacitor there will be an impedance in the circuit.  Now the impedance of the coil increases as the frequency gets higher and the impedance of the capacitor gets higher as the frequency gets lower.  An AM tuning circuit simply passes the signal current through both a coil and a capacitor at the same time, and the capacitor is a mechanically variable one, so by turning a knob you can increase or decrease the capacitance.  The trick here is that as the capacitance changes the circuit will show least impedance to a specific frequency compared with all the others, so provided the frequencies are not too close, as the law requ
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Why is this on a BIOLOGY quiz? It's a physics question.\n\nAnyway, the short answer is that microwaves are absorbed preferentilaly by certain materials, most commonly by water. Because most foods conatin water they can absorb the microwaves. The microwaves excite the water molecules producing heat and cooking the food.
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Yes. A satellite signal will go through glass and plastic but not solid objects and it will bounce of metal objects. It is possible you might recieve a slight loss in signal strength
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Radio waves store the information in the amplitude and frequency of the wave.\n\nIt is similar to how the voltage in a computer to create the 1s and 0s that make up the information you see on the screen.
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Radio signals, both AM and FM typically carry farther at night due to temperature layering of the atmosphere, which causes the radio waves heading to outer space reflect back down to earth. It's an atmospheric skip effect.
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The Electro magnetic radiation passes through a medium depending upon the frequency of the ray, permeability and permittivity of the medium.\n\nIt has maximum speed in vaccum. In any othe medium it may be reflected, refracted .  The speed in any medium is less than in vaccuum. With in the medium it may be absorbed or may even pass through them.\n\nXray passes throuh almost any medium.\n\nRadio waves are almost reflected. If enters a meduim it is  absorbed easily.
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According to Maxwell's laws, one type of field can induce the other and vice versa. This makes electromagnetic waves possible.
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They are alll electromagnetic waves.  They all have different frequencies.  Radio waves have the lowest and gamma rays have the highest.
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Electromagnetic radiation is a propagating wave in space with electric and magnetic components. These components oscillate at right angles to each other and to the direction of propagation.\n\nThe term electromagnetic radiation is also used as a synonym for electromagnetic waves in general, even if they are not radiating or travelling in free space. This sense includes, for example, light travelling through an optical fiber, or electrical energy travelling within a coaxial cable.\n\nElectromagnetic (EM) radiation carries energy and momentum which may be imparted when it interacts with matter.
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they cause electromagnetic stroms
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By realeasing photons that travel at the speed of about 3*10^8meters per second and carry energy that have frequencies which are visible to the human eye (colors). the frequencies are so high and wavelengths soo low that it can only travel in a straight line. when they hit objects they are bounced back with diferent frequencies depending on the atoms capability to absorb light thus the light from the body is scattered in all directions in a straight line and that is why we see things. and that is why black is the absence of light and also when there is no light there is a shadow blackening of the enviroment by the use of light.
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Radio has to do with sound waves and LASER has to do with light.  I suppose you could cobble up something using both technologies, but what is the point.  I mean fibre optics and radio signals have little in common other they can be used to transfer information.