Ohm's Law: Master the Relationship Between Voltage, Current, and Resistance

Question 1

What is the unit of measurement for resistance?

Accepted Answer

Ohms

Answer

Volts

Answer

Amperes

Answer

Watts

Question 2

A circuit has a voltage of 12 volts and a resistance of 6 ohms. What is the current flowing through the circuit?

Accepted Answer

2 amps

Answer

8 amps

Answer

18 amps

Answer

Cannot be determined from the given information

Question 3

What is the primary purpose of a voltmeter?

Accepted Answer

To measure voltage

Answer

To measure current

Answer

To measure resistance

Answer

To measure capacitance

Question 4

A light bulb has a resistance of 100 ohms. If the voltage across the bulb is 120 volts, what is the current flowing through the bulb?

Accepted Answer

1.2 amps

Answer

0.12 amps

Answer

12 amps

Answer

120 amps

Question 5

What is the relationship between power (P), voltage (V), and current (I) in an electrical circuit?

Accepted Answer

P = V x I

Answer

P = V ÷ I

Answer

P = I ÷ V

Answer

They are not related

Question 6

According to Ohm's Law, how does current (I) relate to voltage (V) and resistance (R)?

Accepted Answer

I is directly proportional to V and inversely proportional to R

Answer

I is inversely proportional to V and directly proportional to R

Answer

I is directly proportional to R and inversely proportional to V

Answer

I is inversely proportional to R and directly proportional to V

Question 7

What unit is used to measure electrical resistance?

Accepted Answer

Ohm (Ω)

Answer

Ampere (A)

Answer

Watt (W)

Answer

Volt (V)

Question 8

In a circuit where the voltage remains constant, how does doubling the resistance affect the current?

Accepted Answer

It halves the current

Answer

It doubles the current

Answer

It has no effect on the current

Answer

It quadruples the current

Question 9

Which of the following is NOT a factor that influences the resistance of a conductor?

Accepted Answer

Color

Answer

Material composition

Answer

Cross-sectional area

Answer

Length

Question 10

A circuit has a voltage of 12V, a current of 3A, and a resistance of 4Ω. What is the power consumed in this circuit?

Accepted Answer

18W

Answer

12W

Answer

36W

Answer

48W

Question 11

When two resistors with resistances R1 and R2 are connected in parallel, what is the equivalent resistance?

Accepted Answer

1 / (R1 + R2)

Answer

R1 + R2

Answer

R1 - R2

Answer

R1 / R2

Question 12

What is the primary purpose of using a multimeter to measure resistance?

Accepted Answer

To determine whether a circuit is open or closed

Answer

To calculate the current flowing through a circuit

Answer

To measure the voltage across a component

Answer

To test for signal strength

Question 13

According to Ohm's Law, what is the direct relationship between voltage and current, assuming constant resistance?

Accepted Answer

Current increases as voltage increases

Answer

Current decreases as voltage increases

Answer

Current remains unchanged as voltage increases

Answer

Cannot be determined

Question 14

A simple electrical circuit has a voltage of 12 volts and a resistance of 6 ohms. Calculate the current flowing through the circuit.

Accepted Answer

2 amps

Answer

0.5 amps

Answer

6 amps

Answer

12 amps

Question 15

A 100-ohm resistor has a current of 0.2 amps flowing through it. What is the voltage drop across the resistor?

Accepted Answer

20 volts

Answer

100 volts

Answer

200 volts

Answer

400 volts

Question 16

Which unit is used to measure electrical resistance?

Accepted Answer

Ohm

Answer

Volt

Answer

Ampere

Answer

Watt

Question 17

A series circuit consists of two resistors. The first resistor has a resistance of 10 ohms and the second resistor has a resistance of 15 ohms. Calculate the circuit's total resistance.

Accepted Answer

30 ohms

Answer

5 ohms

Answer

10 ohms

Answer

25 ohms

Question 18

Which equation represents Ohm's Law?

Accepted Answer

V = IR

Answer

I = VR

Answer

R = VI

Answer

V + I + R = 0

Question 19

Which of the following is the SI unit for electrical resistance?

Accepted Answer

Ohm (Ω)

Answer

Volt (V)

Answer

Ampere (A)

Answer

Watt (W)

Question 20

A resistor with a resistance of 10 ohms (Ω) is connected to a 12-volt (V) battery. What is the current (I) flowing through the resistor?

Accepted Answer

1.2 amps (A)

Answer

0.12 amps (A)

Answer

12 amps (A)

Answer

120 amps (A)

Question 21

A voltmeter is used to measure:

Accepted Answer

Voltage (V)

Answer

Current (I)

Answer

Resistance (R)

Answer

Power (P)

Question 22

Which of the following is NOT a safety precaution when working with electrical systems?

Accepted Answer

Working on live circuits

Answer

Wearing proper safety gear

Answer

Using insulated tools

Answer

Testing circuits before making repairs

Question 23

According to Ohm's Law, how are voltage (V), current (I), and resistance (R) related in an electrical circuit?

Accepted Answer

V is directly proportional to I and inversely proportional to R.

Answer

V is directly proportional to I and R.

Answer

I is directly proportional to V and R.

Answer

I is inversely proportional to V and R.

Question 24

According to Ohm's Law, which of the following correctly defines voltage?

Accepted Answer

The force that drives electrons throughout a circuit

Answer

The total amount of electrical energy stored within a circuit

Answer

The number of electrons flowing through a circuit per unit time

Answer

The resistance encountered by electrons as they move through a circuit

Question 25

Within Ohm's Law, what unit of measurement is used to express current?

Accepted Answer

Amps

Answer

Volts

Answer

Ohms

Answer

Watts

Question 26

If the resistance present in an electrical circuit decreases, what corresponding change occurs to the current?

Accepted Answer

An increase

Answer

A decrease

Answer

No change

Answer

Impossible to determine

Question 27

Which of the following factors does NOT influence the resistance of a conductor?

Accepted Answer

The voltage applied to the conductor

Answer

The material composition of the conductor

Answer

The length of the conductor

Answer

The temperature of the conductor

Question 28

A wire having a resistance of 10 ohms is cut into two equal halves. What is the resistance of each resulting half?

Accepted Answer

5 ohms

Answer

10 ohms

Answer

15 ohms

Answer

20 ohms

Question 29

What is a primary advantage of utilizing parallel circuits?

Accepted Answer

Increased current handling capacity

Answer

Increased voltage

Answer

Reduced overall resistance

Answer

Simplified troubleshooting procedures

Question 30

In a series circuit, how is the total resistance calculated?

Accepted Answer

It is equal to the sum of the resistances of all individual components.

Answer

It is less than the resistance of any individual component.

Answer

It is greater than the resistance of any individual component.

Answer

It depends on the voltage present in the circuit.

Question 31

In a circuit, what is the power dissipated when the resistance is 5 ohms and the current is 2 amps?

Accepted Answer

20 watts

Answer

10 watts

Answer

40 watts

Answer

80 watts

Question 32

Which of the following instruments is used to measure voltage?

Accepted Answer

Voltmeter

Answer

Ammeter

Answer

Ohmmeter

Answer

Wattmeter

Question 33

You're designing the taillight circuit for a car.  Using Ohm's Law, how do you figure out the correct resistor to use for the right brightness?

Accepted Answer

Figure out the taillights' needed current, pick a battery, and use Ohm's Law to find the right resistor.

Answer

Measure the taillights' resistance and use an adjustable resistor to control the power to them.

Answer

Try different resistors until the taillights are the right brightness.

Answer

Check the car maker's instructions for the taillight system and use their suggested resistor.

Question 34

The unit of resistance in the International System of Units (SI) is the:

Accepted Answer

Ohm

Answer

Ampere

Answer

Volt

Answer

Coulomb

Question 35

In an electrical circuit, if the voltage across a resistor is doubled while the resistance remains constant, the current will:

Accepted Answer

Double

Answer

Halve

Answer

Quadruple

Answer

Remain the same

Question 36

A circuit with a voltage of 12 volts and a resistance of 6 ohms has a current of:

Accepted Answer

2 amperes

Answer

6 amperes

Answer

12 amperes

Answer

Cannot be determined without additional information

Question 37

Which component in an electrical circuit is used to regulate the flow of current?

Accepted Answer

Resistor

Answer

Capacitor

Answer

Inductor

Answer

Transistor

Question 38

In a voltmeter, a shunt resistor is used to:

Accepted Answer

Reduce the current flowing through the meter

Answer

Increase the voltage reading

Answer

Prevent damage to the meter

Answer

Calibrate the meter

Question 39

In a series circuit, adding a resistor will:

Accepted Answer

Increase the total resistance

Answer

Decrease the total resistance

Answer

Leave the total resistance unchanged

Answer

Depend on the resistance of the added resistor

Question 40

In a series circuit, the total resistance is the:

Accepted Answer

Sum of individual resistances

Answer

Average of individual resistances

Answer

Product of individual resistances

Question 41

Which factors influence the resistance of a conductor?

Accepted Answer

Length, cross-sectional area, and material composition

Answer

Temperature, humidity, and altitude

Answer

Weight, color, and shape

Answer

Voltage, current, and power

Question 42

In a series circuit, the total resistance is:

Accepted Answer

The sum of the individual resistances

Answer

The product of the individual resistances

Answer

The average of the individual resistances

Answer

The difference between the individual resistances

Question 43

The unit of resistance in the International System of Units (SI) is:

Accepted Answer

Ohm

Answer

Volt

Answer

Ampere

Answer

Watt

Question 44

A circuit has a voltage of 10 volts, a current of 1 amp, and a power of 10 watts. What is the resistance of the circuit?

Accepted Answer

10 ohms

Answer

20 ohms

Answer

8 ohms

Answer

15 ohms

Question 45

The SI unit for measuring electric current is:

Accepted Answer

Ampere

Answer

Watt

Answer

Volt

Answer

Ohm

Question 46

If the voltage in a circuit remains constant and the resistance is increased, what happens to the current?

Accepted Answer

The current decreases.

Answer

The current increases.

Answer

The current becomes zero.

Answer

The current remains the same.

Question 47

According to Ohm's Law, the current flowing through a conductor is:

Accepted Answer

Directly proportional to the voltage and inversely proportional to the resistance.

Answer

Inversely proportional to the voltage and directly proportional to the resistance.

Question 48

In an electrical circuit, a high resistance typically means:

Accepted Answer

Reduced current flow.

Answer

Enhanced circuit efficiency.

Answer

Increased voltage drop.

Answer

Stable power consumption.

Question 49

What is the formula for Ohm's Law, which describes the relationship between voltage, current, and resistance?

Accepted Answer

V = I * R

Answer

I = V / R

Answer

V = R / I

Answer

R = V / I

Question 50

An automotive circuit has a voltage of 12 volts and a current of 3 amps flowing through it. What is the resistance of the circuit?

Accepted Answer

4 ohms

Answer

15 ohms

Answer

6 ohms

Answer

36 ohms

Question 51

Which of the following factors directly affects the resistance of a wire used in an electrical circuit?

Accepted Answer

Length of the wire

Answer

Voltage applied to the wire

Answer

Power dissipated by the wire

Answer

Current flowing through the wire

Question 52

A wire with a resistance of 10 ohms is cut exactly in half. What is the resistance of each of the resulting pieces?

Accepted Answer

5 ohms

Answer

10 ohms

Answer

2.5 ohms

Answer

20 ohms

Question 53

What is the standard unit of measurement for resistance in electrical circuits?

Accepted Answer

Ohm

Answer

Volt

Answer

Watt

Answer

Ampere

Question 54

A 9-volt battery is connected to a resistor with a resistance of 3 ohms. Calculate the current flowing through this circuit.

Accepted Answer

3 amps

Answer

27 amps

Answer

1 amp

Answer

6 amps

Question 55

Which of the following materials is commonly used in automotive electrical systems due to its excellent conductivity?

Accepted Answer

Copper

Answer

Rubber

Answer

Plastic

Question 56

What is the standard unit of measurement for electrical potential difference, commonly known as voltage?

Accepted Answer

Volt

Answer

Ohm

Answer

Ampere

Answer

Watt

Question 57

How are voltage, current, and resistance related to each other in an electrical circuit?

Accepted Answer

Voltage is directly proportional to both current and resistance.

Answer

Current is directly proportional to voltage and inversely proportional to resistance.

Answer

Voltage is inversely proportional to current and resistance.