S302, Kewley-Port 9/22/07
IMPEDANCE, EXPONANTS & LOGARITHMS
1. a) Write down the equation for calculating mass reactance, Xm .
b) Explain how Xm changes with frequency.
c) If frequency is high, how important is Xm in calculating total impedance?
d) If Xm = Xc for some system, and R = 2 ohms, explain the relation between the total impedance and the observed vibration of the system. Will the system be in natural vibration?
2. Consider the following parameters of a system. The resistance R=10 ohms, the mass reactance Xm= 22 ohms, and the compliant reactance Xc = 2 ohms. (a) Draw tttthe viector relationship with accurate lengths of the vectors that looks like Fig. DKP-1 in the handout. (b) Compute the magnitude of the impedance, Z.
3. Solve the following problems using the laws of exponents.
4. Solve the following problems using the laws of logarithms