Science & Principles RA04

What is the conventional flow of current?

• From negative to positive in an open circuit

• From negative to positive in a closed circuit

• From positive to negative in an open circuit

• From positive to negative in a closed circuit

Which of the following electrical terms is correct?

• The symbol for Impedance is Z and it is measured in Amperes

• The symbol for Impedance is X and it is measured in Ohms

• The symbol for Impedance is Z and it is measured in Ohms

• Impedance, which has a symbol A, is measured in Amperes

What is the formula to calculate Impedance?

• Z = R² + X²

Which of the following would be the correct value for 72,000,000 watts?

• 72 Giga watts

• 72 kilo watts

• 72 milli watts

• 72 Mega Watts

Which of the following values would represent 36μΩ?

• 0.00036Ω

• 0.0036Ω

• 0.000036Ω

What is the current flowing in a circuit when a voltage of 230V is applied and two resistors of 28.75Ω each are connected in series?

• 8 Amperes

• 4 Amperes

• 0.125 Amperes

• 0.25 Amperes

What is the power dissipated when two 23Ω resistors are connected in parallel across a 230 volt supply?

• 4.6 kW

• 460 W

• 46000 W

• 2.3 kW

What is the potential difference across each of the four 20 Ω resistors when they are connected in parallel to a 230V supply?

• 11.5 V

• 11.5 A

• 230 V

• 230 A

What is the value of a resistor connected in series with two other resistors of 2.6Ω and 3.8Ω that gives a total resistance of 25Ω

• 18.6Ω

• 3.2Ω

• 11.55Ω

• 5.8Ω