Physics

Electrical Machines and Circuits

720 Questions

Electrical machines and circuits involve the principles of alternating and direct current, transformers, diodes, and power consumption. These concepts are essential for engineering and technical exams. Review these practice questions to test your knowledge of circuit analysis.

Transformers and impedanceAlternating and direct currentCircuit components and diodesPower consumption calculations

Electrical Machines and Circuits Questions

Multiple choice general knowledge science & technology
  1. Farad

  2. Ohm

  3. Henry

  4. Watt

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The SI unit of inductance is the Henry (H), named after Joseph Henry. Farad is the unit of capacitance, Ohm is the unit of resistance, and Watt is the unit of power.

Multiple choice general knowledge science & technology
  1. Volt

  2. Ohm

  3. Coulomb

  4. Watt

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The SI unit of power is the Watt (W), named after James Watt. Volt is the unit of electric potential, Ohm is the unit of resistance, and Coulomb is the unit of electric charge.

Multiple choice general knowledge
  1. Fuse

  2. Main Board

  3. Neighbour's House

  4. Bulb

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When encountering a power failure, the standard troubleshooting sequence is: first check if neighbours have power (to determine if it's a grid-wide issue or isolated to your home), then check your main switch/fuse box. Checking neighbours first helps quickly diagnose whether to call the utility company or check your internal wiring. This is a practical home maintenance question.

Multiple choice general knowledge
  1. 200-250

  2. 300-350

  3. 400-650

  4. 500-550

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Electrophorus electricus (electric eel) can generate discharge voltages ranging from 400 to 650 volts. This high-voltage shock is used for both hunting prey and self-defense. Lower ranges like 200-250 are insufficient for the maximum capacity of a mature specimen.

Multiple choice general knowledge
  1. 100-150

  2. 200-250

  3. 400-650

  4. 300-350

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Electric eels (Electrophorus electricus) are capable of generating electric shocks up to 600-860 volts, with 400-650V being the most accurate range among the options. The lower ranges (100-150V, 200-250V) severely underestimate their power, while 300-350V is still below their maximum documented capacity.

Multiple choice general knowledge science & technology
  1. True

  2. False

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DC (Direct Current) power supply has zero frequency because the current flows in one direction only, unlike AC (Alternating Current) which periodically reverses direction. Frequency is the number of cycles per second, and DC has no oscillation or cycles.

Multiple choice general knowledge science & technology
  1. True

  2. False

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DC (Direct Current) power supply has zero frequency because the current flows in one direction only, unlike AC (Alternating Current) which periodically reverses direction. Frequency is the number of cycles per second, and DC has no oscillation or cycles.

Multiple choice general knowledge science & technology
  1. True

  2. False

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DC (Direct Current) power supply has zero frequency because the current flows in one direction only, unlike AC (Alternating Current) which periodically reverses direction. Frequency is the number of cycles per second, and DC has no oscillation or cycles.

Multiple choice general knowledge science & technology
  1. Power Capacitors

  2. Regulators

  3. Voltage stabilizers

  4. Current stabilizers

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Voltage stabilizers are designed to manage power fluctuations by maintaining a constant output voltage despite variations in input voltage. Regulators and capacitors serve different purposes, while 'current stabilizers' is not a standard term.