# Investigation Into How the Depth of Water Affects the Speed of a Wave

INVESTIGATION INTO HOW THE DEPTH OF WATER

AFFECTS THE SPEED OF A WAVE

Aim

To find how the depth of water affects the speed of a wave.

Waves are vibrations (or oscillations) moving through something - a

medium. As a wave passes, each bit of the medium vibrates in turn. The

vibrations appear to move through the medium. Each bit of the medium in

turn vibrates/oscillates, but stays where it is. The wave transfers energy as

it moves. The medium can be matter (solid, liquid, gas). This is the case

for water waves.

There are two types of wave:

a) Transverse waves. The vibrations are at right angles to the direction of

the wave.

b) Longitudinal waves. The vibrations are along the same direction as the

waves.

The waves I will be studying are transverse waves.

During a previous experiment I found that a drop height of 5cms and to

allow the wave to do 3 laps of the container before stopping the

stopwatch was the best course of action. 5cms is a good height because it

is high enough to cause a strong wave, but not high enough to create water

to spill over the container's edge. I chose 3 laps because after that the

wave starts to lose momentum and slows down.

Apparatus

Container

Stopwatch

Ruler

Water

Prediction

I predict that the greater the depth of water, the faster the waves will travel.

The reason for this is that when the water is shallow, the container bottom

begins to interfere with water motion. The bottom constrains the water

motion and results in a dragging affect on the waves. Also, the deeper the

water the greater the mass and therefore force of the wave, which creates

more momentum and speed. I have chosen the depths ...