Question

C'mon... Help a brother out...
What important safety precaution must be observed when measuring resistance in an electronic circuit?
A. The black test lead must be connected to the chassis ground.

B. The red test lead must be at the most positive point in the circuit.

C. The meter's highest resistance range setting should be used until the actual value is determined.

D. All power to the component under test must be disconnected.

Answer 1

D. All power to the component under test must be disconnected.

Answer 2

Answer:

D. All power to the componet under the test must be disconnected

Explanation:

When measuring in an electronic circuit, it is important to keep in mind that the are some values can only be measured when the circuit is on, for exmple voltage drop on a component or current flow, however there are other values which requires the circuit to be disconnected of  any source of power as is the case of resistance. This is so because  measuring resistance is carried out by injecting power to the element to measure using our ohmmeter. If we do not disconnect the circuit from the power source, we will get false readings and probaly will affect or even damage the ohmmeter if the power is strong enough.