1. MEE …. WAVE PROPAGATION IN SOLIDS Week 1 Assoc. Prof. Dr. Abdullah Seçgin

2. A Harmonic wave.. Wavelength..

3. Wave Speed For solids: For gas (not for liquids):

4. Example: Speed of sound Ex.1.1: Compute the speed of sound waves for air at 20 0 C, and for steel? For air: For steel: or simply

5. Particle velocity Surface of the source expands and contracts sinusoidally During the first half of the motion, it pushes the particles near its surface outward During the second half of the motion, it pulls the particles near its surface inward. It is the velocity of the oscillation of the particle, so not be confused with wave speed which is the velocity of the propagating wave. Particle velocity can be longitudinal (compression), or transverse Particles Source

6. Longitudinal-Transverse waves

7. Propagation of Waves in 1D to the leftto the rightWave propagates Wavenumber The wave propagates with k in space and with in time

8. A little math.. Gradient, Divergence, Curl, Laplacian

9. Examples Derive the followings