What is meant by the term resonance? How would resonance be demonstrated in the laboratory? A set of wind chimes, as shown in the diagram, is made from different lengths of hollow metal tubing that are open at both ends - Leaving Cert Physics - Question 7 - 2013

To demonstrate resonance, one might use apparatus such as Barton's pendulum, which consists of a column of air and a tuning fork. The procedure can involve setting one pendulum oscillating and bringing a vibrating fork near it to observe the energy transfer.

The identified frequencies 550 Hz, 1100 Hz, and 1651 Hz are known as overtones or harmonics.

For each frequency:

• 550 Hz: The tube has an antinode (A) at both ends, with a node (N) at the center.
• 1100 Hz: The tube has antinodes at both ends, linked correctly to one node in the center.
• 1651 Hz: The tube has antinodes at both ends, linked correctly to three nodes within the tube.

Using the formula for the speed of sound in a tube:

$v = f imes ext{wavelength}$

For the fundamental frequency (550 Hz):

• The length of the tube is 0.60 m (30 cm).
• Therefore, the speed of sound is: $v = 550 ext{ Hz} imes 0.60 ext{ m} = 330 ext{ m/s}$.

Using the formula for the tension of a string:

\rho = 0.004 ext{ kg/m}
T = \frac{4 \times 0.64 \times (173)^2}{0.004}
T = 196 ext{ N}