General Properties of Waves

On Fig. 5.1, mark the centre of a compression with the letter C, and mark the centre of a rarefaction with the letter R.

Describe the difference between a compression and a rarefaction.

The wooden bar makes 45 complete oscillations in $1.0\ \text{minute}$.

Calculate the frequency of the wave produced.

frequency = ______ $\text{Hz}$

The frequency of the water wave is increased by moving the wooden bar up and down more quickly.

State what happens to the speed and what happens to the wavelength of the wave produced.

speed ______
wavelength ______

The crests of the water wave move into the shallow region shown in Fig. 5.2.

On Fig. 5.2, draw the crests in the shallow region.

Describe what is meant by the diffraction of a water wave.

State one way in which the student's drawing of the crests is wrong.

The gap in the barrier is now made smaller than the wavelength, as shown in Fig. 7.2.

Complete Fig. 7.2 with at least three crests to show the new diffraction pattern.

Define the term 'wavelength'.

Calculate the frequency of the wave.

frequency = ______ $\text{Hz}$

Calculate the wavelength of the wave in the shallow part of the tank.

wavelength = ______ $\text{cm}$

Underline two other examples of transverse waves.

seismic P-waves      seismic S-waves      sound      X-rays

The speed of the water wave is $27\text{ cm / s}$.

Calculate the frequency and the wavelength of the wave.

frequency = ______ $\text{Hz}$
wavelength = ______ $\text{cm}$

The wave diffracts at the right-hand edge of the glass block.

On Fig. 5.1 draw two crests after they pass the glass block to show the diffraction.

Describe how a wave with a smaller wavelength is made with the wooden bar.

Describe how a decrease in wavelength affects the diffraction.

Calculate the wavelength in air of this red light.

wavelength = ______ $\text{m}$

State what happens to the speed, to the frequency and to the wavelength of the light as it enters the block.

speed ______
frequency ______
wavelength ______

Using the angles shown on Fig. 4.1, calculate the refractive index of the glass.

refractive index = ______

The light continues along the path shown in Fig. 4.1 until it strikes the bottom surface of the block. Light then emerges into the air.

Draw on Fig. 4.1 to show the path taken by the light until it strikes the bottom surface and the path of the light that emerges into the air.

Draw a diagram of a ripple tank and describe how it is used to produce and observe the wave.

The water wave in the ripple tank transfers energy.

Describe how to show that there is a transfer of energy.

State what is meant by a wavefront.

State one difference and one similarity of the two waves.

difference ______

similarity ______

the frequency of wave P,

frequency = ______

the wavelength of wave P.

wavelength = ______

Light is a transverse wave. The direction of vibration is perpendicular to the direction of transfer of the energy.

Complete the table of Fig. 5.1 to show the direction of vibration and the type of wave associated with a sound wave and with a wave on the surface of water in a ripple tank.

Fig. 5.1

Determine the amplitude of the vibration at $\text{time} = 0.25\text{ s}$.

Describe how the graph shows that the frequency of the wave is constant.

Describe the movement of the particles of the string.

Determine the wavelength of the wave.

wavelength = ______

Calculate the frequency of the wave.

frequency = ______

On Fig. 4.1, draw the string at a time $0.10\ \text{s}$ later than the time in Fig. 4.1.

Explain what is meant by the frequency of a wave.

Determine the wavelength of the wave in deep water.

Calculate the speed of the wave in deep water.

speed = ______

State and explain how this affects the wavelength of the wave.

The wave in deep water shown in Fig. 9.2 travels towards the right and enters the shallow water at an angle. The wave refracts.

On Fig. 9.2, draw the wavefronts in the shallow water.

Describe one difference between a sound wave and a water wave.

The speed of sound in carbon dioxide gas is less than the speed of sound in air. Using this information, or otherwise, describe an experiment to show the refraction of sound waves. You may include a diagram of your apparatus.

mark the direction of movement of the student's hand,

mark and label the wavelength $\lambda$ of the wave,

mark and label the amplitude $A$ of the wave.

Describe how the frequency of the wave is found using a stopwatch.

Using the same rope, the student produces a wave of a longer wavelength than that shown in Fig. 4.1.

State how the student does this.