Knowledge Quiz

The current use for charging storage batteries is

• direct

• alternating

• negative

• positive

Answer explanation

The correct answer is 'direct' because storage batteries are typically charged using direct current (DC), which allows for a consistent flow of electricity, essential for effective charging.

An electric current is pushed thru a conductor by

• voltage

• amperage

• ohms

• watts

Answer explanation

An electric current is driven through a conductor by voltage, which creates the potential difference needed for the flow of electrons. Amperage measures the current, ohms measure resistance, and watts measure power.

Current flow is measure in

• voltage

• amperage

• ohms

• watts

Answer explanation

Current flow is measured in amperage, which quantifies the amount of electric charge passing a point in a circuit per unit time. Voltage measures potential difference, ohms measure resistance, and watts measure power.

To use a voltmeter, it must be placed in ____________

Answer explanation

To measure voltage accurately, a voltmeter must be placed in parallel with the component or circuit being tested. This allows it to measure the potential difference without affecting the circuit's operation.

What will limit current flow?

• resistance

• Capacitance

• wattage

• inductance

Answer explanation

Resistance limits current flow by opposing the movement of electrons in a circuit. Higher resistance results in lower current, according to Ohm's Law (V=IR), making resistance the key factor in controlling current.

Power used in a circuit is measure in

• Amps

• Volts

• watts

• ohms

Answer explanation

Power in a circuit is measured in watts, which is the product of voltage (volts) and current (amps). Therefore, the correct answer is watts.

Current flow through a wire coil wrapped around a steel core will cause the core to become?

• overheated

• shorted

• magnetic

Answer explanation

When current flows through a wire coil around a steel core, it generates a magnetic field, magnetizing the core. This phenomenon is known as electromagnetism, making the correct answer 'magnetic'.

A megger is used to check the

• wattage

• breakdownvoltage

• resistance

• amperage capacity

Answer explanation

A megger is specifically designed to measure electrical resistance, particularly in insulation testing. It applies a high voltage to check for insulation breakdown, making 'resistance' the correct answer.

What is the purpose of a fuse in a circuit?

• to limit voltage

• to limit resistance

• to limit wattage

Answer explanation

A fuse is designed to limit wattage in a circuit by breaking the connection when the current exceeds a certain level, preventing overheating and potential damage. This makes 'to limit wattage' the correct choice.

In all installations, the guiding factors determining all aspects of a wiring job are found in

• the blueprint

• The National Electric Code

• verbal instruction

• written orders

Answer explanation

The National Electric Code (NEC) provides the essential guidelines and standards for electrical installations, ensuring safety and compliance. It is the primary reference for all wiring jobs, making it the correct choice.