7. The diagram shows a waveform. (i) What is the name given to the distance (a) X, (b) Y? (ii) What is meant by the frequency of a wave? (iii) Explain the term natural frequency?
(iv) If the natural frequency of a vibrating string is 250 Hz, calculate the wavelength of the sound produced.
(v) State the wave property on which (c) the loudness, (d) the pitch, of a musical note depends.
An opera singer singing a high-pitched note can shatter a glass. Explain why.
X
(6) (6) (6)
(9) (9)
Resonance can occur between objects of the same natural frequency.
(6)
Describe a laboratory experiment to demonstrate resonance. (14) (c = f λ, speed of sound in air = 340 m s−1)
2009 7.
In an experiment a beam of monochromatic light passes through a diffraction grating and strikes a screen.
(i) Explain the underlined terms.
diffraction grating
laser screen (ii) Describe what is observed on the screen. (6)
(iii) Explain, with the aid of a diagram, how this phenomenon occurs. (14)
(iv) What does this experiment tell us about the nature of light?
(6)
(v) Name the property of light that can be determined in this experiment.
(6)
(vi) What measurements must be taken to determine the property you named?
