How are radio waves transmitted using an antenna?
What will be an ideal response?
Radio waves are usually transmitted and received using an antenna. An antenna is a length of copper wire, or similar material, with one end free and the other end connected to a receiver or transmitter. When transmitting, the radio waves created by the electronic circuit of the transmitter are fed to this antenna wire. This sets up an electrical pressure (voltage) along the wire, which will cause a small electrical current to flow into the antenna. Because the current is alternating, it flows back and forth in the antenna at the same frequency as the radio waves. When the electricity moves back and forth in the antenna at the same frequency as the radio waves, it creates both a magnetic field and an electrical field around the antenna. This continuous (analog) combination of magnetism and electrical pressure moves away (propagates) from the antenna the same way that water waves move away from the point of impact when you throw a rock in a pond. The result is an electromagnetic wave (EM wave).
You might also like to view...
In the accompanying figure, what happens when power is applied to the stator?
What will be an ideal response?
______________ are devices that can store electrical energy, similar to a battery.
a. Relays b. Motors c. Transformers d. Capacitors
All of the following statements are true EXCEPT:
A. shocks often fail at the same rate. B. a defective shock absorber can cause a tire to "hop." C. a leaking shock can be the result of a defective seal or from lowering a vehicle too far. D. a damaged piston rod on a Macpherson strut causes a leak. This can result from holding the rod with pliers during installation of the top nut.
Technician A says that when adjusting a spray gun, the atomized coating coming out of the gun cap should be a fine mist with small droplets of spray. Technician B says that when refinishing a vehicle, its original orange peel texture should be matched. Who is correct?
A. Technician A only B. Technician B only C. Both Technicians A and B D. Neither Technician A nor B