Pennies today are copper-covered zinc, but older pennies are 3.1 g of solid copper. What are the total positive charge and total negative charge in a solid copper penny that is electrically neutral?
• 17.1 what is light 3 models ‣ Wave model-light travels in wave like patterns • Known as wave optics ‣ Ray model • Light travels in a straight line ‣ Photon model • Light consists of photons that have both wavelike and particle like properties The propagation of light waves ‣ Spreading of waves is called diffraction • Waves spread out from the opening rather than continuing in a straight line ‣ Wavelength of light is short ‣ How far a light wave spreads out depends on the size of the objects with which the wave interact ‣ Light has a dual nature • sometimes it looks like a wave while other times it l
