LED circuit with current-limiting resistor in PCB Design - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate the resistor value using Ohm's Law.

PCB Design

resistor_value = (supply_voltage - led_voltage) / [1]

Drag options to blanks, or click blank then click option'

Avoltage

Bled_current

Cpower

Dresistance

Attempts:

3 left

💡 Hint

Common Mistakes

Using voltage instead of current in the denominator.

Confusing power with current.

The resistor value is calculated by dividing the voltage difference by the LED current, according to Ohm's Law.

2fill in blank

medium

Complete the code to convert LED current from milliamps to amps.

PCB Design

led_current = [1] / 1000

Drag options to blanks, or click blank then click option'

Aled_current_mA

Bled_voltage

Cresistor_value

Dsupply_voltage

Attempts:

3 left

💡 Hint

Common Mistakes

Using voltage instead of current for conversion.

Multiplying by 1000 instead of dividing.

Current in milliamps is divided by 1000 to convert to amps for calculations.

3fill in blank

hard

Fix the error in the resistor power calculation.

PCB Design

power_dissipated = (led_current ** 2) * [1]

Drag options to blanks, or click blank then click option'

Aresistor_value

Bled_voltage

Csupply_voltage

Dled_current

Attempts:

3 left

💡 Hint

Common Mistakes

Using voltage instead of resistance.

Using current instead of resistance.

Power dissipated by the resistor is current squared times the resistor value.

4fill in blank

hard

Fill both blanks to calculate the resistor value and power dissipation.

PCB Design

resistor_value = ([1] - led_voltage) / led_current
power_dissipated = (led_current ** 2) * [2]

Drag options to blanks, or click blank then click option'

Asupply_voltage

Bled_voltage

Cresistor_value

Dled_current

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up voltage and current in formulas.

Using LED voltage instead of supply voltage for resistor calculation.

First, calculate resistor value by subtracting LED voltage from supply voltage and dividing by current. Then calculate power using current squared times resistor value.

5fill in blank

hard

Fill all three blanks to calculate resistor value, power dissipation, and check if resistor power rating is sufficient.

PCB Design

resistor_value = ([1] - [2]) / [3]
power_dissipated = ([3] ** 2) * resistor_value
is_safe = power_dissipated < resistor_power_rating

Drag options to blanks, or click blank then click option'

Asupply_voltage

Bled_voltage

Cled_current

Dresistor_value

Attempts:

3 left

💡 Hint

Common Mistakes

Using resistor value as current.

Mixing up voltage variables.

Calculate resistor value by subtracting LED voltage from supply voltage and dividing by LED current. Power dissipated is current squared times resistor value. Then check if power dissipated is less than resistor's power rating.