Chapter 22, Problem 107A

To determine

To identify: two difference parabolic graphs to describe a circuit’s power.

Explanation of Solution

Introduction:

The electric power is the ability to do work in driving the current through component when a potential difference is applied. In other words, electric power is the current time the potential difference between the terminals of the component.

The equation for the electric power is given by the following formula,

  $P=I\Delta V$  ......(1)

Here, $I$ and $\Delta V$ are the current flowing through the component and the applied potential difference.

To understand the concept of non-ohmic substance we should derive the graph firstly for power and voltage and secondly power and current.

For non-ohmic substance, the graph is non linear like a parabolic. The graph between the power and the voltage is below for a diode.

  

The graph below is between power and the current in the diode (non-ohmic substance)

  

As both the graph are non linear, so the slope is not constant. It varies from point to point along the graph.