Waves and Vibrations physics. I'm so glad this time we can share the material Physics: Vibration and Waves along with examples of problems and discussion, Please be informed.
A. VIBRATION
1. Definition of Vibration
A. Definition
Vibration is the motion of alternating - bolik periodically through a balance point. In general, every object can do vibration. An object is said to vibrate when it moves back and forth periodically
B. Some Vibration Examples
Some examples of vibrations that we can encounter in everyday life include: - guitar rays are picked - pendulum wall clock - the swing of the children being played - a plastic ruler is clamped at one end, then the other end is deviated by pulling it, then released the pull. - Spring loaded.
2. Period and Vibration Frequency
Look at the following picture!
- Point A is the balance point
- The largest pendulum of the pendulum (designated by distance AB = AC) is called the vibration amplitude
- The distance B - A - C - A - B is called one full vibration
A. Amplitude
In Figure 2 it has been mentioned that the amplitude is the largest deviation calculated from a balanced position. Amplitude is given the symbol A, with units of meters.
B. Vibration Period
The vibration period is the time used in one vibration and given the symbol T. For the swing image above, if the time required by the pendulum to move from B to A, to C, to A, and back to B is 0.2 second, then The vibration period of the pendulum is 0.2 seconds or T = 0.2 sec = 0.2 s
The period of a vibration is independent of the vibrational amplitude.
C. Vibration Frequency
Vibration frequency is the amount of vibration performed by the system in one second, given the symbol f. For the pendulum swing system above, if in the time required by the pendulum to move from B to A, A to C, C to A, and return to B equal to 0.2 sec, then:
- within 0.2 seconds the pendulum undergoes one full vibration
- within 1 sec pendulum undergo 5 times the full vibration
It is said that the vibrational frequency of the pendulum system is 5 vibrations/sec or f = 5 Hz.
D. Relationship between Period and Vibration Frequency
From the definition of the period and frequency of the above vibrations, the relationship is obtained:
Information :
T = period, the units are seconds or seconds
F = frequency of vibration, units of 1 / sec or s-1 or Hz
Problems example :
1. In 1 second, the path traveled in Figure 1 is 2-1-3-1-2-1-3. What is the frequency and period of the vibration?
Resolution:
The number of vibrations that occur is 1.5 vibrations.
The time to travel 1.5 vibrations is 1 second.
So the frequency f = 1.5 vibration / sekon = 1.5 Hz. And period T:
So the time required to take one full vibration is 0.67 seconds.
2. At intervals of 2 seconds there is a movement back and forth as much as 10 times. Determine the frequency and period.
Resolution:
In 2 seconds 10 vibrations occur. Means that in 1 second there are 5 vibrations,
so the frequency f = 5 Hz, and period T:
B. WAVES
1. Understanding Waves
Waves are the propagation phenomenon of a vibration. The waves will continue to occur when this vibration source vibrates continuously. Waves carry energy from one place to another. A simple example of a wave, when we attach one end of the rope to the pole, and one end of the rope is again shaken, it will form many hills and valleys in the rope shaken earlier, this is called a wave.
B. TYPES OF WAVES
1. Based on the Medium The wave is divided into two, namely:
a. Mechanical Waves
Mechanical waves are waves which in the process of propagation require a medium (intermediate matter). This means that if there is no medium, then the wave will not occur. An example is a Sound Wave whose airborne aerial agent, so if no sound of the sound will not be heard.
b. Electromagnetic wave
Electromagnetic waves are waves that in the process of propagation do not require a medium (intermediate substances). This means that this wave can propagate under any circumstances without the need for medium. An example is a continuous light wave and does not require an intermediate.
2. Based on the direction of vibration and direction propagation, Wave is divided into two, namely:
a. Transverse Waves
Transverse wave is a wave whose direction of vibration is perpendicular to the direction of its propagation. Vibration shapes form valleys and hills.
Based on the picture above I can explain that:
The direction of wave propagation above is to the left and to the right, while the direction of vibration is up and down. So that's what the creep direction is perpendicular to the direction of vibration.
Examples of transverse waves:
- the vibrations of the picked git rays
- the vibrations of the rope are shaken at one end
b. Longitudinal Waves
Longitudinal waves are waves whose rambatnya parallel to the direction of vibration. The form of vibration is dense and tenuous.
Based on the picture we know that:
The direction of wave propagation to the left and to the right, and the direction of vibration to the left and right as well. Therefore these waves are longitudinal waves with vibration direction and parallel propagation direction.
Examples of these waves are sound waves, in the air that this wave surge will occur dense and tenuous on its molecules, and when there is a propagation of these molecules also vibrate. But the velocity is only limited to move back and stay in balance point, so as not to form hills and valleys.
3. Based on Amplitude (the farthest intersection) The wave is also divided into two:
a. Walking Waves
A running wave is a wave whose amplitude is fixed at every point through which a wave passes, for example a wave on a rope.
b. Quiet wave
The silent wave is a wave whose amplitude changes, for example a wave on the strings of a picked guitar.
Thus the material of Physics: Vibration and Waves along with examples of problems and discussion that we can convey. Hope can increase our knowledge.
