Physics 2009 JAMB Past Questions - Question 28: Metal cables are used as telephone wires because

Correct Answer

D

Explanation

Metal cables, often referred to as "copper wires," have historically been used as telephone wires for several reasons:

1. Conductivity: Metals such as copper and aluminum are excellent conductors of electricity. This conductivity allows for the transmission of electrical signals, which are used to carry voice and data over telephone lines.

2. Low Resistance: Copper wires, in particular, have low electrical resistance. This means that electrical signals can travel long distances without significant loss of signal strength, which is crucial for telephone communication.

3. Durability: Copper wires are durable and can withstand various environmental conditions, making them suitable for outdoor installations. They are resistant to moisture, corrosion, and physical damage.

4. Ease of Installation: Copper wires are relatively easy to install, making them a cost-effective choice for telecommunications infrastructure.

5. Compatibility: Copper wires have been used in telecommunication systems for decades, and many existing telephone networks are built on this technology. This historical legacy has contributed to their continued use.

It's worth noting that while copper wires have traditionally been the standard for telephone communication, modern telecommunications systems are increasingly transitioning to fiber optics, which offer even higher data transmission speeds and bandwidth. Fiber optic cables use pulses of light to transmit data, making them more suitable for high-speed internet and other data-intensive applications. However, copper wires are still in use in many areas, particularly for traditional landline phone services and in regions where fiber optic infrastructure is not yet available.