The cell phone was invented in 1973, and during the first 20 years of its life, few people use one, except as a car phone. But during the 1990s, the use of cell phones increased dramatically and the price of cell phone service fell.
A, Are there any substitutes for cell phones? If so, provide an example.
B, do cell phones have any complements? If so, provide an example.
C, what are the main developments that brought about the dramatic increase in cell phone use during the 1990s?
D, which of the developments that you have identified increased the demand for cell phones? Illustrate these effects by using the demand curve for cell phones.
E, which of the developments that you have identified increased the quantity demanded of cell phones? Illustrate these effects by using demand curve for cell phones.
Answers
AnswerCell phones send signals to (and receive them from) nearby cell towers (base stations) using RF waves. This is a form of energy in the electromagnetic spectrum that falls between FM radio waves and microwaves. Like FM radio waves, microwaves, visible light, and heat, RF waves are a form of non-ionizing radiation. They don’t have enough energy to cause cancer by directly damaging the DNA (genes) inside cells. RF waves are different from stronger (ionizing) types of radiation such as x-rays, gamma rays, and ultraviolet (UV) rays. Ionizing radiation can break the chemical bonds in DNA, which might lead to cancer.
The electromagnetic spectrum illustration shows the possible frequencies of electromagnetic energy, ranging from extremely low frequencies (such as those from power lines) to exposures from extremely high frequencies (x-rays and gamma rays), and includes both non-ionizing and ionizing radiation.: