JAMB Physics 2024 Paper

Concept:When two sound waves of slightly different frequencies are sounded together, periodic loudness variation called beats is produced. The beat frequency is the absolute difference between the two frequencies.Explanation:The beat frequency is given by the formula:$$\text{Beat frequency} = |f_1 - f_2|$$Here, the first tuning fork has frequency $f_1 = 6\,\text{Hz}$.The second tuning fork has frequency $f_2 = 4\,\text{Hz}$.Substitute the values into the formula:$$\text{Beat frequency} = |6\,\text{Hz} - 4\,\text{Hz}|$$$$\text{Beat frequency} = 2\,\text{Hz}$$Therefore, the listener hears $2$ beats per second when the two forks are sounded together.Answer:The beat frequency is $2\,\text{Hz}$, which corresponds to option A.