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ANSWERS TO QUESTIONS Q1. THROUGH Q70.
A1. Circuit measurement is used to (1) monitor the operation of a piece of electrical or electronic
equipment and (2) determine the reason a piece of electrical or electronic equipment is not
functioning properly.
A2. In-circuit meters are used to monitor the operation of electrical or electronic devices.
A3. Out-of-circuit meters can be used on more than one electrical or electronic device.
A4. The compass needle swings away from magnetic north and aligns itself with the magnetic field
around the conductor.
A5. If the current increases the magnetic field increases; if the current decreases the magnetic field
decreases.
A6. The compass needle will not be deflected as far from magnetic north.
A7. A permanent-magnet moving-coil meter movement used in most electrical and electronic meters.
A8. A magnetic field is generated around the coil and the attraction of this field with the permanent
magnet causes the coil to move.
A9. To return the pointer to its rest position when there is no current flow; to oppose the coil movement
when there is current flow; to provide electrical connections for the coil.
A10. The compass needle would swing back and forth as the current changed from positive to negative.
A11. The compass needle would vibrate rapidly around the zero-current point ac meter (magnetic
north).
A12. A rectifier changes alternating current to pulsating direct current and allows a dc meter to
measure ac.
A13. By the use of a rectifier
A14. The process of "smoothing out" the oscillation in a meter movement.
A15. As the coil moves through the field of the permanent magnet, a current is induced in the coil
opposing the movement of the coil; and a vane can be attached to the coil and placed in the airtight
chamber so that the movement of the vane opposes the movement of the coil.
A16. Average value.
A17. Effective value (rms).
A18. Electrodynamic, moving vane, and hot-wire or thermocouple.
A19. Current.
A20. Current.
A21. In series.
