Electrotechnics

Standard for AC voltage in our region is:

• 110V with 60Hz

• 110V with 50 Hz

• 230V with 60 Hz

• 230V with 50Hz

An electric generator is an electrical machine that converts _________ energy into _________ energy.

• electrical-mechanical

• mechanical-electrical

• electrical-fluid

• electrical-electronic

What is correct order in electricity transmission:

Power plant (1)

Transmission lines (2)

Step down transformer (3)

Step up transformer (4)

Homes (5)

• 1-4-2-3-5

• 1-4-3-2-5

• 4-1-3-2-5

• 4-1-2-3-5

Electric current is measured in volts (V).

• True

• False

Thermal power station is a power station in which heat energy is converted to electric power.

• True

• False

Plastic and dry wood are very good electrical conductors.

• True

• False

____________ electricity is more efficient and less expensive for long-distance electricity transmission. _____________ electricity is safer for use in homes and businesses.

• Higher voltage-Lower voltage

• Lower voltage-Higher voltage

• AC current-DC current

• DC current-AC current

Conventional current flow is from positive to negative terminal.

• True

• False

If U=7V and I=2A, how much is P?

• 9W

• 14N

• 14W

• 9N

Oil and natural gas are renewable sources of energy.

• True

• False