PHYSICS · Multi-part · Fermi University Physics · Scientific Practice & Experimental Methods · Oscillations, Waves & Acoustics · Quantities, units and the practice of measurement
Measurement and Method, Ch What dimensions decide before you measure anything
Problem
A transverse wave travels along a taut string. The relevant quantities are judged to be the tension in the string, F (unit N), and the mass per unit length of the string, μ (unit kgm−1).
((a)) Write v=CFαμβ for the wave speed v, with C a dimensionless constant, and use dimensional homogeneity to find α and β.
((b)) For a string with F=40N and μ=1.0×10−3kgm−1, evaluate v in terms of C.
((c)) The full wave equation (not derivable from dimensions alone) gives C=1 for this problem. State the numerical wave speed to two significant figures.