21. Which one of the following statements is true for voltage in a parallel circuit?
A. The total voltage in a parallel circuit is equal to the average value of the individual voltages
B. The total voltage in a parallel circuit is always less than the value of the smallest voltage
C. The total voltage is equal to the sum of the voltages across the individual branches in a parallel circuit
D. The total voltage of a parallel circuit is the same as the voltages across each branch
E. None of the above
22. The dielectric constant of a material is a measure of:
A. the amount of voltage it can withstand before breaking down
B. how well the material concentrates electrostatic lines of force
C. the amount of opposition to the current flow
D. how well the material concentrates magnetic lines of force
E. None of the above
23. What is the inductive reactance of a 2-H coil operating at 60 Hz?
A. 754 Ohm
B. 30 Ohm
C. 60 Ohm
D. 120 Ohm
E. None of the above
24. When operating above its resonant frequency, a series RLC circuit has the characteristics of a:
A. series RL circuit
B. series RC circuit
C. series RLC circuit operated below its resonant frequency
D. purely resistive circuit
E. None of the above
25. What is the primary difference between primary and secondary cell batteries?
A. Primary-cell batteries can be recharged and used many times, whereas secondary-cell batteries cannot be properly recharged
B. Secondary-cell batteries can be recharged and used many times, whereas primary-cell batteries cannot be properly recharged
C. Primary-cell batteries use chemical cells, whereas secondary-cell batteries use an alternative energy source, such as thermal or magnetic energy, to supplement their outputs
D. Primary-cell batteries must be recharged at a much slower rate that secondary-cell batteries
E. None of the above