Aresearcher places dogs in a cage with metal bars on the floor. the dogs are randomly given electric shocks and can do nothing to prevent them or stop them. later, the same dogs are placed in a cage where they can escape the shocks by jumping over a low hurdle. when the shocks are given, the dogs do not even try to escape. they just sit and cower. this is an example of

when the displaced particles are perpendicular to the direction the wave travels, is called a transverse wave, whereas in longitudinal wave the displace practices are parallel to the direction of the wave.

in the given image:

first image shows - longitudinal wave

second image shows - transverse wave

third image shows - longitudinal wave

fourth image shows - longitudinal wave