Final answer:
Current and resistance are kept low to prevent excess heat. Low resistance is vital for safety, longevity of electronic components, and energy efficiency. To increase power dissipation with constant current, resistance should be reduced.
Step-by-step explanation:
The question you asked is related to the properties of electrical circuits, specifically concerning why current and resistance are kept low. The answer is a. To prevent excess heat. When current flows through a resistor, electrical energy is converted to heat due to the resistance of the material, according to the formula P=I2R where P is power, I is current, and R is resistance. Keeping current and resistance low minimizes heat generation, which is critical for the safety and longevity of electronic components and to prevent energy waste.
If you wanted to increase the power dissipated in a circuit, with the current kept constant, you would choose to reduce the resistance. This is because power dissipation in a resistor increases as resistance decreases when current is held constant. This is aligned with the power formula P=V2/R, indicating that for a fixed voltage, power is inversely proportional to resistance.