Doppler Effect Demonstration Apparatus, 92dB buzzer, 0.8m tether. Nylon cord is 2ft 8in attached to a rugged ABS handle 8.5in long, (1in diameter), Swing the apparatus and students will be able to hear the change in frequency, Dimensions: 4.5 x 5 x 3 in
Harmonic Motion Spring, ideal for demonstrations or hands on experiments in the physics classroom, 7 inches (18 cm) long with a maximum diameter of 1.4 inches (3.5 cm) and a spring constant (k) of 9.6 N/m