radio waves are electromagnetic waves that travel at the speed of light 300 000 kilometers per second what is the wave length of FM radio waves received 100 megahertz on your radio dial

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.

a.   mass number from atomic number