Series Circuit Flashcards
What is standard form or scientific notation?
A number written with one digit to the left of the decimal point and multiplied by 10 raised to some power.
What is engineering notation?
Similar to scientific notation except that the power of ten is always a multiple of 3.
Convert 12345 to scientific notation.
1.2345 x 10^4
Convert 12345 to engineering notation.
12.345 x 10^3
Convert 0.321 to scientific notation.
3.21 x 10^-1
Convert 0.321 to engineering notation.
321 x 10^-3
Convert 0.000012 to scientific notation.
1.2 x 10^-5
Convert 0.000012 to engineering notation.
12 x 10^-6
What happens when converting from a larger unit to a smaller unit?
Move the decimal point to the right.
Convert 0.47 MW to kW.
470 kW
Convert 10,000 pF to mF.
0.01 mF
When adding or subtracting numbers with metric prefixes, what should you do first?
Convert them to the same prefix.
What is Ohm’s Law?
The current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to its resistance.
What is the formula for Ohm’s Law?
V = I × R
If voltage increases while resistance remains constant, what happens to current?
Current increases.
If resistance increases while voltage remains constant, what happens to current?
Current decreases.
Calculate the current in a circuit with a 12 V source and a resistance of 10 Ohms.
1.2 A
What is the voltage across a 680 Ohm resistor if the current is 26.5 mA?
18.02 V
Calculate the resistance of a rear window defroster grid with a 12.6 V battery drawing 15 mA.
840 Ohms
What is the relationship between energy and power?
Power is the rate at which energy is used.
What is the formula for power?
P = W / t
One watt is equivalent to how much energy used in one second?
One joule.
What is the unit of energy?
Joule (J)
What is kilowatt-hour (kWh)?
The use of 1000W of power per 1 hour.
Calculate the energy used by a 1200 W heater for 20 minutes.
0.4 kWh
What is Watt’s Law?
The relationship between power, voltage, and current.
What is the power dissipated in a 27 Ohm resistor if the current is 0.135 A?
0.49 W
What is the power rating of a resistor?
The max amount of power a resistor can dissipate without damage.
How is the total resistance of resistors in series calculated?
RT = R1 + R2 + R3 + … + Rn
What is the same through all points in a series circuit?
The current.
What is the total voltage in a series circuit of voltage sources?
The algebraic sum of the individual sources.
What happens to the total current if the total resistance in a series circuit increases?
The total current decreases.
Calculate the total resistance of a circuit with 56 Ohm, 100 Ohm, 27 Ohm, 10 Ohm, and 47 Ohm resistors.
240 Ohm
What do you use to determine the total current in a series circuit?
Ohm’s Law.
How do you find the voltage drop across a resistor in a series circuit?
V = I × R
What is the effect of the voltage drop across a resistor in terms of polarity?
Positive at the end closest to the positive terminal of the voltage source.
What is the total current if the total resistance is 9.5 kOhm and the voltage is 9.5 V?
1 mA
What is the formula for calculating total source voltage in a series circuit?
𝑉𝑆(𝑡𝑜𝑡) = 𝑉𝑆1 + 𝑉𝑆2 + ⋯ + 𝑉𝑆𝑛
What does Kirchhoff’s Voltage Law (KVL) state?
The sum of all voltage drops around a single closed path in a circuit is equal to the total source voltage in that closed path.
True or False: KVL applies to all circuits but must be applied to only one closed path.
True
How is KVL mathematically expressed?
n ∑Vi = 0, i=1
What is the first step in finding the unknown resistor R4 in a circuit?
Use Ohm’s Law to find the voltage drop across each known resistor.
What is the formula for calculating voltage drop across a resistor?
𝑉 = 𝐼 × 𝑅
Calculate V4 if the total source voltage is 50V and known voltage drops are 1V, 4.7V, and 10V.
V4 = 34.3V
How do you calculate the resistance R4 if the voltage drop V4 is 34.3V and current I is 10mA?
R4 = V4 / I = 3.43kΩ
What is the voltage drop across a given resistor in a series circuit?
The voltage drop is equal to the ratio of that resistor to the total resistance, multiplied by source voltage.
What is the formula to find total resistance RT in a series circuit?
RT = R1 + R2 + … + Rn
What is the Voltage Divider Rule?
Voltage across a resistor is V = VS × (RX / RT)
Find the voltage V1 across R1 (82Ω) when the source voltage VS is 10V and total resistance RT is 150Ω.
V1 = 5.47V
If the voltage V1 is 5.47V and V2 is 4.53V, what should the sum equal?
The sum V1 + V2 should equal VS.
What is the formula for voltage VAB if R1 is 1kΩ and RT is 12.5kΩ with a source voltage of 25V?
VAB = VS × (R1 / RT) = 2V
Determine the voltage VBC if R2 is 8.2kΩ and total resistance RT is 12.5kΩ with a source voltage of 25V.
VBC = 16.4V
What is the definition of Ohm’s Law?
A law stating that current is directly proportional to voltage and inversely proportional to resistance.
What is energy measured in?
The unit is the joule (J).
What is the unit of power?
The unit of power is the watt (W).
What does an Ampere-hour rating indicate?
It is determined by multiplying the current (A) times the length of time (h) that a battery can deliver that current.
What is a series circuit?
A relationship of components in which the components are connected such that they provide a single path between two points.
What is a voltage divider?
A circuit consisting of series resistors across which one or more output voltages are taken.
What is Kirchhoff’s Voltage Law?
The sum of the voltage drops around a closed loop equals the source voltage in that loop.
