PASCO WA-9857 String Vibrator - Manual (Page 22)

String Vibrator Teachers’ Notes–Wave Speed
22 ®
Tension
F = 10.4 N
Wave Speed Calculated from Wavelength and Frequency
Stretched Length = L = 2.343 m
Number of segments = 4
λ = 1.172 m
f = 60.0 Hz
v =
λ f = 70.2 m/s
Wave Speed Calculated from Tension and String Density
The unstretched length measured in this part of the experiment will be less than the unstretched
length measured initially because of the knots tied in the ends.
Unstretched Length (with knots) = 1.162 m
µ = 2.11 × 10
-3
kg/m
Speed of a Single Pulse
The sudden decrease in tension may appear on the graph as a sudden decrease or increase in force,
depending on whether the force sensor is set up to register tension as a positive or negative force.
v
F
µ
--- 70.2 m/s = =