A uniform wire, fixed at both ends, is plucked in the middle so that it vibrates at the first harmonic as shown.

What is the phase difference between the oscillations of the particles at P and Q?

Which shows the change in velocity, frequency and wavelength of an electromagnetic wave as it travels from an optically less dense to an optically more dense medium?

The graph shows how the vertical height of a travelling wave varies with distance along the path of the wave.

The speed of the wave is 20 cm s^–1.

What is the period of the wave?

A progressive wave of frequency 150 Hz travels along a stretched string at a speed of 30 m s⁻¹.

What is the phase difference between two points that are 50 mm apart on the string?

For waves on a water surface, the following graph shows how the displacement y of a water particle in the surface varies with the time t.

What are the quantities z and s?

Two coherent sources generate sound waves of wavelength 0.40 m. The waves leave the sources in phase. A detector some distance from the sources receives the sound waves. The path difference between the detector and the sources is 0.90 m.

What is the phase difference between the waves arriving at the detector?

Two points on a progressive wave are one-eighth of a wavelength apart. The distance between them is 0.5 m, and the frequency of the oscillation is 10 Hz. What is the minimum speed of the wave?

Sound waves cross a boundary between two media X and Y. The frequency of the waves in X is 400 Hz. The speed of the waves in X is 330 m s^–1 and the speed of the waves in Y is 1320 m s^–1. What are the correct frequency and wavelength in Y?

The diagram shows two pulses on a string travelling towards each other.

Which of the following diagrams shows the shape of the string when the pulses have passed through each other?

What is the phase difference between two points 0.16 m apart on a progressive sound wave of frequency 256 Hz?

speed of sound = 330 m s^–1

The diagram shows a snapshot of a wave on a rope travelling from left to right.

At the instant shown, point P is at maximum displacement and point Q is at zero displacement.

Which one of the following correctly describes the motion of P and Q in the next half-cycle?

The speed of sound in water is 1500 m s⁻¹. For a sound wave in water having frequency 2500

Hz, what is the minimum distance between two points at which the vibrations are π/3 rad out of phase?

Two points on a progressive wave differ in phase by π/4. The distance between them is 0.5 m, and the frequency of the oscillation is 10 Hz. What is the minimum speed of the wave?

Which line, A to D, in the table gives a correct difference between a progressive wave and a stationary wave?

A wave of frequency 5 Hz travels at 8 km s^–1 through a medium. What is the phase difference, in radians, between two points 2 km apart?

A source emits light of wavelength 600 nm as a train of waves lasting 0.01 µs. How many complete waves are sent out?

speed of light = 3 × 10⁸ m s⁻¹

The graph shows, at a particular instant, the variation of the displacement of the particles in a transverse progressive water wave, of wavelength 4 cm, travelling from left to right. Which one of the following statements is not true?

The audible range of a girl's hearing is 30 Hz to 16 500 Hz. If the speed of sound in air is 330 m s⁻¹, what is the shortest wavelength of sound in air which the girl can hear?

A wave motion has period T, frequency f, wavelength λ and speed ʋ. Which one of the following equations is incorrect?

A progressive wave in a stretched string has a speed of 20 m s⁻¹ and a frequency of 100 Hz.

What is the phase difference between two points 25 mm apart?

The least distance between two points of a progressive transverse wave which have a phase difference of π/3 rad is 0.050 m. If the frequency of the wave is 500 Hz, what is the speed of the wave?

Two waves with amplitudes a and 3a interfere.

The ratio in the image is