Combination of Resistors and Electrical Power

What are combination circuits?

• Circuits with variable resistors

• Circuits with only series resistors

• Circuits with only parallel resistors

• Circuits with a combination of series and parallel resistors

When finding the total resistance in a combination circuit, what should be found first in some situations?

• The current through the resistors

• The total resistance of the series resistors

• The total resistance of the parallel resistors

• The voltage across the resistors

what is the total resistance of the parallel combination of two 50 ohm resistors?

• 100 ohms

• 75 ohms

• 50 ohms

• 25 ohms

What is the top tip given for simplifying calculations when two or more resistors in parallel have the exact same value?

• Subtract the resistance values from each other

• Divide the value of one resistor by the total number of resistors

• Add the resistance values together

• Multiply the value of one resistor by the total number of resistors

If there were three 100 Ω resistors in parallel, what would be the total resistance using the top tip given?

• 50 ohms

• 16.67 ohms

• 33.33 ohms

• 25 ohms

What caution is given regarding the top tip for simplifying calculations in parallel resistors? (divide by the number of branches)

• The shortcut only works for variable resistors

• The shortcut only works for series resistors

• The shortcut only works if the resistance values are identical

• The shortcut only works if the resistance values are different

What is the formula for calculating the total resistance of resistors in parallel?

• rt = r1 + r2 + r3

• 1/rt = 1/r1 + 1/r2 + 1/r3

• rt = r1 / r2 / r3

• rt = r1 * r2 * r3

What happens to the total resistance when more resistors are added in parallel?

• Cannot be determined

• Increases

• Decreases

• Remains the same

What is the total resistance of resistors in parallel compared to the smallest resistance value?

• Smaller

• Greater

• Depends on the number of resistors

• Equal

What is the total resistance when three resistors of 10 ohms, 20 ohms, and 20 ohms are connected in parallel?

• 15 ohms

• 10 ohms

• 30 ohms

• 5 ohms