# Compute current, voltage, resistance, and power, using Ohm's law and Watt's law.

## Definition

Computation requires an understanding of the mathematical and scientific concepts related to Watt’s law and power and should include- defining the terms of the equation for Ohm's law and Watt's law:
- Ohm's law: V = IR; I = V/R; R = V/I
- Watt’s law: P = VI; I = P/V; V = P/I
- describing the basic scientific principle that
- if resistance to current flow stays the same and the voltage pressure increases, the current flow rate must also increase.

## Process/Skill Questions

- What is
*Watt’s law*? - What are the mathematical relationships of Watt’s law?
- How can Watt’s law be used to evaluate circuit characteristics?
- What are the units of measurement involved in Watt’s law, and what is their relationship to one another?
- How do Ohm’s law and Watt’s law relate to each other in the analysis of electronic circuits?

## Related Standards of Learning

## Mathematics

### A.4

The student will solve

- multistep linear and quadratic equations in one variables algebraically;
- quadratic equations in one variables algebraically;
- literal equations for a specified variable;
- systems of two linear equations in two variables algebraically and graphically; and
- practical problems involving equations and systems of equations.

### A.6

The student will

- determine the slope of a line when given an equation of the line, the graph of the line, or two points on the line;
- write the equation of a line when given the graph of the line, two points on the line, or the slope and a point on the line; and
- graph linear equations in two variables.

### A.8

The student, given a situation in a real-world context, will analyze a relation to determine whether a direct or inverse variation exists, and represent a direct variation algebraically and graphically and an inverse variation algebraically.

### AII.3

The student will solve

- absolute value linear equations and inequalities;
- quadratic equations over the set of complex numbers;
- equations containing rational algebraic expressions; and
- equations containing radical expressions.

### AII.10

The student will represent, create, and solve problems, including practical problems, involving inverse variation, joint variation, and a combination of direct and inverse variations.

## Science

### PH.11

The student will investigate and understand how to diagram, construct, and analyze basic electrical circuits and explain the function of various circuit components. Key concepts include

- Ohm’s law;
- series, parallel, and combined circuits;
- electrical power; and
- alternating and direct currents.