Un pistón genera ondas con frecuencias de 70 hz. la velocidad de dichas ondas es de 10 m/s hacia la izquierda, y tienen una amplitud de 0.03 m.
halla:
- el periodo de onda;
- la longitud de onda;
- el número de onda y frecuencia angular;
- la altura de la onda (teniendo en cuenta que x = 1 m y t = 1 s).

Athin plate moves between two parallel, horizontal, stationary flat surfaces at a constant velocity of v = 7.5 m/s. the two stationary surfaces are spaced 4 cm apart, and the medium between them is filled with oil whose viscosity is 0.9 n·s/m2. the part of the plate immersed in oil at any given time is 2 m long and 0.5 m wide. if the plate moves through the mid-plane between the surfaces, determine the force required to maintain this motion. what would your response be if the plate was 1 cm from the bottom surface (h2) and 3 cm from the top surface (h1)? if the plate moves through the mid-plane between the surfaces, the force required to maintain the motion will be n. if the plate was 1 cm from the bottom surface (h2) and 3 cm from the top (h1) surface, the force required to maintain the motion would be n.