AMPLITUDEBUILDING UTILITIES 3

DE LA LUNA, MARGARETTE A.2013120415

AMPLITUDE• measures how far a wave rises and

falls. • A wave's amplitude is defined as

half the distance from its highest point to its lowest point. • Amplitude is proportional to the

energy of a wave, a high energy wave having a high amplitude and a low energy wave having a low amplitude.

AMPLITUDE“Imagine a wave in the ocean.

It could be a LITTLE ripple or a GIANT tsunami.

What you are actually seeing are waves with different amplitudes.• They might have the exact

same frequency and wavelength, but the amplitudes of the waves can be very different.

AMPLITUDE• The amplitude of a wave is

measured as:

1. The height from the equilibrium point to the highest point of a crest or

2. The depth from the equilibrium point to the lowest point of a trough

AMPLITUDE• When you measure the amplitude

of a wave, you are really looking at the energy of the wave.• It takes more energy to make a

bigger amplitude wave.• Anytime you need to remember

this, just think of a home stereo’s amplifier… it makes the amplitude of the waves bigger by using more electrical energy.

WAVELENGTH• Wavelength is a property of a wave that

most people (once they know what to look for) can spot quickly and easily, and use it as a way of telling waves apart. • Any of the parts of the wave that are

pointing up like mountains are called crests. Any part that is sloping down like a valley is a trough.• Wavelength is defined as the distance

from a particular height on the wave to the next spot on the wave where it is at the same height and going in the same direction

How is the Energy Transported Related to the Amplitude?

• The amount of energy carried by a wave is related to the amplitude of the wave. • A high energy wave is

characterized by a high amplitude; a low energy wave is characterized by a low amplitude. • The amplitude of a wave refers to

the maximum amount of displacement of a particle on the medium from its rest position.

How is the Energy Transported Related to the Amplitude?

• The logic underlying the energy-amplitude relationship is as follows: • If a slinky is stretched out in a horizontal

direction and a transverse pulse is introduced into the slinky, the first coil is given an initial amount of displacement. The displacement is due to the force applied by the person upon the coil to displace it a given amount from rest. The more energy that the person puts into the pulse, the more work that he/she will do upon the first coil. The more work that is done upon the first coil, the more displacement that is given to it. The more displacement that is given to the first coil, the more amplitude that it will have.

How is the Energy Transported Related to the Amplitude?

• So in the end, the amplitude of a transverse pulse is related to the energy which that pulse transports through the medium. Putting a lot of energy into a transverse pulse will not effect the wavelength, the frequency or the speed of the pulse. The energy imparted to a pulse will only affect the amplitude of that pulse.

Energy-Amplitude Mathematical Relationship

The energy transported by a wave is directly proportional to the square of the amplitude of the wave. This energy-amplitude relationship is sometimes expressed in the following manner. LARGER AMPLITUDE

=MORE SEVERE =MORE ENERGY

The amplitude of a light's wave is important because it tells you about the intensity or brightness of the light relative to other light waves of the same wavelength. It's a measure of how much energy the wave carries.

So, if the light from Star A is brighter than the same type of light from Star B, you know that the light you see from Star A has the larger amplitude. Its very important to note that while amplitude gives you information about the intensity of the light, it is the wavelength, not the amplitude, that tells you what kind of light it is.

Importance of Amplitude

Remember,Wavelength tells you the type of light

And,Amplitude tells you about the intensity

of the light