# Waves, Sound and Light: Light Waves

## Light Waves: Audio Guided Solution

#### Problem 12:

Water waves with a wavelength of 7.8 cm are created in a ripple tank by two in-phase sources bobbing up and down at the same frequency. The waves form an interference pattern in the space surrounding the sources. A point on the fourth nodal line is a distance of 58.2 cm from the nearest source. Determine the distance from this same point to the furthest source.

## Habits of an Effective Problem Solver

• Read the problem carefully and develop a mental picture of the physical situation. If necessary, sketch a simple diagram of the physical situation to help you visualize it.
• Identify the known and unknown quantities and record in an organized manner, often times they can be recorded on the diagram itself. Equate given values to the symbols used to represent the corresponding quantity (e.g., v = 3.00x108 m/s, λ = 554 nm, f = ???).
• Use physics formulas and conceptual reasoning to plot a strategy for solving for the unknown quantity.
• Identify the appropriate formula(s) to use.
• Perform substitutions and algebraic manipulations in order to solve for the unknown quantity.