3_7 Resistance and Resistors

The resistance of a material is.

• independent of the material type.

• the same as its conductance.

• the reciprocal of its conductance.

Resistance is measured using what unit of temperature?.

• Absolute.

• Centigrade.

• Fahrenheit.

A resistor has 4 bands on it coloured blue, yellow, yellow, gold. It's value is.

• 640 kΩ ± 5%.

• 6.4 mΩ ± 10%.

• 64 kΩ ± 5%.

The electron flow through a conductor will be decreased the most if the cross sectional area.

• is decreased and the length is increased.

• and the length are both decreased.

• and the length are both increased.

Small resistors too small or mis-shapen for the application of colour are marked instead using.

• an abbreviated resistance value.

• a letter code.

• a dot code.

Total resistance in a parallel resistor circuit, of R1 and R2 is.

• RT = 1/R1 + 1/R2.

• 1/RT = (R1 * R2) ÷ (R1 + R2).

• 1/RT = 1/R1 + 1/R2.

If the resistance of a resistor which is in series with two other resistors is doubled.

• the current in that resistance is doubled.

• the volts drop across that resistor increases.

• the current in that resistance is halved.

The total resistance of the circuit shown is.

• 3 Ohms.

• 1.33 Ohms.

• 12 Ohms.

Potentiometers are used as a.

• variable voltage source.

• variable resistor.

• variable current source.

In a Wheatstone Bridge, the ammeter reads zero, and the variable resistor is adjusted to 5 ohms. Resistor P has a value of 10 ohms and Q has a value of 100 ohms. What is the value of the unknown resistor?.

• 5 ohms.

• 0.5 ohms.

• 50 ohms.