What is resistance ?
In physics, the term resistance is defined as a substance’s ability in preventing or “resisting” the flow of electrical current. This type of resistance occurs because atoms and electrons collide, slowing down the electrons and converting some of the energy into heat. In other instances, energy is transformed into light.
Other substances are more resistant than the rest. For instance, plastics could resist more than copper; meaning, electricity flows less readily through plastics, than it does in copper, which is considered a good conductor. Likewise, glass resists more than copper because glass are considered insulators.
One of the large players in the history of physicist is German physicist Georg Ohm, who discovered the effects of a substance’s thickness, length and make up. Ohm, which is the standard unit in measuring resistance, was named after the physicist. In 1827, the Ohm’s law was publicly announced and recorded. There are three important quantities in Ohm’s Law – voltage, current and resistance. The law states that the current can be maximized by having a larger voltage drop and a smaller resistance.
Letters and symbols are used in expressing physics equations. R is used for resistance, so to measure resistance, the equation “R equals V divided by I” is used. In this formula, V is the potential difference of the objects in volts and I is the current which flows through the objects in amperes.
