A wave is represented by an equation . In which direction is the wave going? Assume that c₁, c₂ and c₃ are all positive.

You are walking along a seashore and a mild wind is blowing. Is the motion of air a wave motion?

The radio and TV programmes, telecast at the studio, reach our antenna by wave motion. Is it a mechanical wave or non-mechanical?

Show that the particle speed can never be equal to the wave speed in a sine wave if the amplitude is less than wavelength divided by 2π.

Two wave pulses identical in shape but inverted with respect to each other are produced at the two ends of a stretched string. At an instant when the pulses reach the middle, the string becomes completely straight. What happens to the energy of the two pulses?