Presentation on theme: "Waves Rowena D. Olicia CTP-LEAPPhilippines 4 th Year."— Presentation transcript:
Waves Rowena D. Olicia CTP-LEAPPhilippines 4 th Year
TARGETS At the end of the lesson, 75% of the students should be able to: Define waves. Identify the characteristics of wave. Solve problems on waves.
WAVES are disturbances that propagate through space are also called energy carriers transfer energy from one point to another do not carry the particle of matter only cause particle of matter to vibrate / move back and forth
Parts of Waves Wavelength Amplitude A distance time wave crest wave trough wavelength amplitude
Examples of Waves Water surface waves Sound Electromagnetic Waves (EM Waves) - radio/TV waves, microwave, infrared, visible light, ultraviolet, X-rays, gamma Seismic waves
Characteristics of Waves Frequency f (inverse of period T) number of cycles per second (Hertz) f = c / T = 1 / f T
Wavelength ( λ ) Wavelength ( λ ) distance between successive identical parts of a wave distance the wave has traveled in one complete cycle
Amplitude Maximum displacement from the equilibrium (midpoint) position Measure of how much energy the wave has
Frequency (f) number of waves that pass a given point per unit of time Unit: hertz (Hz)
Period (T) time for a wave to complete a cycle reciprocal of frequency T= 1/f Wave Speed (v) speed with which waves pass a particular point Wave speed = wavelength / period v = λ / T or v = λ f
Sample Problems 1) A vibration of frequency 5Hz sends a wave of 0.8m down a rope. What is the speed of the wave? 2) A wave of wavelength 1.5m travels down a rope at a speed of 6m/s. What is the frequency of the wave?
Solutions 1) Given: frequency (f) = 5Hz wavelength ( λ ) =0.8m speed (v) =? Formula:V =f x V = 5 Hz x 0.8m V = 4.0 m/s
SUMMARY I. Waves disturbances in space/matter energy carriers II. Kinds Mechanical Waves (need a medium) a. longitudinal (propagation parallel to motion) ex. sound b. transverse (propagation perpendicular to motion) ex. String wave EM Waves (do not need a medium) ex. Radio/TV waves, microwave, visible light, UV, X-rays
SUMMARY III. Wave Characteristics Wavelength (crest-crest; trough-trough) Frequency (no. of waves per second) Amplitude (maximum displacement) Period (time to complete one cycle) Wave speed(wavelength over period)