Frederic Bronson, age 5 of Los Angeles, California, for his question:
What is the moon mode of?
There was a time when people said that the moon was made of green cheese. Looking at it shining up there in the sky, you might think it was made of gold maybe a big golden penny.
Actually, the moon is made of rocks and dirt. It is a great ball, though not nearly as big as our Earth. It looks golden to us because we only see the parts of it that are covered with sunshine.
Robert Douchis, age 139 of Hyde Park for his question .
What is high frequency electricity?
We have all heard of direct and alternating currents of electricity. About 50 years agog it was agreed that alternating current was best suited to carry our vast webs of electrical power over the land. For it is easier to step up alternating current when more power is needed m d step it down when too much power would be dangerous. Frequency is a term used in measuring this stepping up bf electrical current for certain high powered jobs.
Both direct and alternating current are caused when pressured or voltage, is applied to a circuit of electrical wire. This voltage power is generated when copper coils pass through a magnetic field. The electrical wires and cables lead off the current and return in a circuit to the generator.
The magic push of voltage affects certain of the minute electrons within the copper wire carrying the current. In facts the electric current is really the movement of these minute electrons. It is thought that the voltage forces them to line up like well trained soldiers and march, The electrons in a direct current ere thought to line up and march directly forward, The marching line is flowing out from the battery or generator clear around the circuit and bank,
In alternating current, the little soldiers alternate their directions first forward then backward. Believe it or no they do this alternating turnabout many times every second. Chances are, the electricity piped to your home is alternating its current at the rate of 60 times a second: Each of these turnabouts is called a cycle and your new toaster may carry a tag saying that it is to be used on a current carrying 60 cycles.
Fast as this seams, it is much too .slow for some of our high powered electrical jobs. Such a current would be useless, for example, for sending out the programs from radio: station. For this jobs the cycles are speeds up and counted in units of kilocycles one thousand cycles equal one kilo cycle. This speeding up is called high frequency.
When a radio station announces that it is broadcasting on a frequency of 760 kilocycles, it means that the electrons in the current of its powerful antenna are rushing back end forth at the rate of 760,000 times a second. The voice of your radio network hero may be sent to you on a high frequency of a million cycles as American broadcasting is done within a frequency range of from 550:000 to 1,600,000.
A ship to shore radio telephone uses even higher frequencies; It must carry electromagnetic waves in unbroken streams if the conversations are to be clear and accurate. This electricity is sometimes generated by very high frequency alternating current generators sometimes by special oscillators capable of generating frequencies of many millions.