Examkin

Question

Difficulty: MediumDirect Current (DC) vs. Alternating Current (AC)

Rechargeable batteries store electrical energy as direct current (DC) and cannot be charged directly from an alternating current (AC) source without first converting the current to DC.

Answer: Answer

Answer

True
Chemical energy storage in batteries relies on unidirectional electron flow (direct current) to sustain the oxidation-reduction reactions necessary for charging. Because alternating current reverses direction at regular intervals, it cannot build up a net chemical charge without first being converted to direct current by a rectifier.

Step-by-Step Solution

1
Identify the operating principle of battery charging and electrochemical energy storage
Chemical batteries operate via fixed-polarity reduction-oxidation reactions, requiring unidirectional direct current (DC) to drive electrons into the negative electrode.
Electrochemical storage depends on electrons flowing consistently in a single direction to reverse cell discharge.
2
Analyze the behavior of alternating current (AC) applied to battery terminals
AC periodically reverses direction (e.g., 60 times per second in a 60 Hz60\text{ Hz} system), attempting to charge during one half-cycle and discharge during the next.
Without converting AC to DC via a rectifier, there is zero net accumulation of chemical charge.
3
Evaluate the validity of the statement
The statement is True.
Batteries store energy as DC and require AC-to-DC conversion (rectification) before charging from an AC source.

Key Concept

Direct current (DC) maintains unidirectional electron flow required for electrochemical storage, whereas alternating current (AC) periodically reverses direction and cannot charge chemical batteries without rectification.
Estimated Time:45s
Rate this question

Topics

Direct Current (DC) vs. Alternating Current (AC)

More questions from this topic