Mention any two advantages of using alternating current over direct current. Why is hydroelectric power generation more environmentally friendly than thermal power generation? [1+2]
WBBSE
Class X
Physical Science
Current Electricity
03 Mark
2026
Two advantages of AC over DC
- AC voltage can be easily increased or decreased using a transformer.
- AC can be transmitted over long distances with less power loss by transmitting it at high voltage.
Hydroelectric power is more environmentally friendly because:
- It uses flowing or stored water, which is a renewable source of energy.
- It does not involve the burning of fossil fuels and hence produces almost no smoke, CO₂ or other harmful gases during electricity generation.
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