Speed of Light
The speed of light is much greater than the speed of sound.
Olaus Roemer --- Danish Scientist, 1st method to find the speed of light, used the planets, he calculated the speed of light was 227,000 kilometers per second
Albert A. Michelson --- 1926, developed a more modern method to determine the speed of light, used mirrors, calculated the speed of light to be 186,285 miles per second (299,796 kilometers per second)
The wavelength of any electromagnetic vibration x its frequency = the speed of the electromagnetic vibration
Scientists have determined that the speed of any electromagnetic vibration = the speed of light (approximate value of the speed of light is 300,000 kilometers per second)
The speed of an electromagnetic wave is not affected by temperature, but it is affected by the medium through which it travels.
Transmission of Light
Light can travel through a vacuum.
Opaque Objects --- completely block light and through which you cannot see
Transparent Objects --- readily transmit light and through which you can see clearly
Translucent Objects --- allow light to pass through partially or that distort the light so that you cannot see through them
Behavior of Light
Light travels in a straight line.
Pinhole Camera --- the object that is viewed is upside-down
Shadow --- the dark space behind an object that is formed when light is blocked by that opaque object
Umbra --- the darker central portion of the shadow that receives no light from the source
Penumbra --- the lighter shadow that surrounds the umbra and receives some light from outer edges of the light source
Presented By: Mary