Capacitors are commonly used to:

• A. Reduce circuit resistance
• B. Improve power factor and smooth voltage fluctuations
• C. Increase current flow
• D. Limit power consumption

Answer: (B)

Capacitors are widely used in electrical circuits primarily for two key functions: improving power factor and smoothing voltage fluctuations.

Improving power factor involves making the circuit more efficient by reducing the phase difference between voltage and current in AC systems. Capacitors provide reactive power needed to counteract the inductive effects of devices such as motors and transformers, thus bringing the power factor closer to unity. This not only enhances the efficiency of power distribution but also helps in reducing energy losses in the system.

Smoothing voltage fluctuations is another critical application of capacitors. In power supply circuits, capacitors act as filters, temporarily storing electrical energy and releasing it when needed. This helps to stabilize voltage levels during fluctuations caused by varying load demands or other disturbances in the network. By maintaining a more stable voltage supply, capacitors improve the overall performance of electrical devices.

While the other options mention important concepts related to electrical circuits, the role of capacitors specifically aligns with enhancing power factor and smoothing out voltage variations, making option B the most accurate representation of their primary uses.