How to use a Resistor - Basic electronics engineering

Summary

This video explains how to combine resistors to achieve specific resistance values in circuits. It covers both series and parallel resistor combinations, demonstrating how to use these methods to increase or decrease resistance. The video also explains how to read resistor values using colored stripes, with examples of both 4-band and 5-band resistors. Viewers learn how to calculate equivalent resistance, interpret the tolerance of resistors, and measure actual resistance with a multimeter. The video concludes with an invitation to explore further content on electronics and electrical engineering.

Takeaways

• 😀 Resistor values that are calculated may not always be available or in stock, so combining resistors can achieve the desired value.
• 😀 To increase the resistor value, resistors are placed in series, while to decrease it, they are placed in parallel.
• 😀 When resistors are placed in series, their values simply add together.
• 😀 When resistors are placed in parallel, an equivalent resistance calculation is required using a specific formula.
• 😀 Example: Two 10 ohm resistors in parallel provide an equivalent resistance of 5 ohms.
• 😀 A combination of resistors, such as two 50 ohm and one 100 ohm resistor, can achieve the desired resistance value.
• 😀 Resistor values can be identified by the colored stripes on the body, which represent the resistance and tolerance.
• 😀 A four-band resistor includes two digit bands, a multiplier band, and a tolerance band.
• 😀 Example of a four-band resistor: brown, black, brown, and gold corresponds to 100 ohms with a tolerance of ±5%.
• 😀 A five-band resistor provides more precision, with the first three bands representing digits, the fourth band as the multiplier, and the fifth as the tolerance.
• 😀 Example of a five-band resistor: orange, orange, black, black, brown corresponds to 330 ohms with a tolerance of ±1%.
• 😀 A multimeter can be used to measure the actual resistance value, which may be within the tolerance range of the resistor's rated value.

Q & A

What happens when you need a resistor value that doesn't exist or is out of stock?

You can combine multiple resistors to achieve the desired value. For example, you can place resistors in series to increase resistance or in parallel to decrease it.

How do resistors behave when connected in series?

In a series combination, the resistor values simply add together. For example, two 100-ohm resistors in series will give a total of 200 ohms.

What is the process to calculate the total resistance when resistors are placed in parallel?

To calculate the total resistance in parallel, use the formula: 1/R_total = 1/R1 + 1/R2 + ... . This results in a lower overall resistance than the individual resistors.

What is the equivalent resistance of two 10-ohm resistors connected in parallel?

The equivalent resistance of two 10-ohm resistors in parallel is 5 ohms, calculated using the parallel resistance formula.

What are the first three bands on a 4-band resistor used for?

The first two bands represent the first two digits of the resistor's value, and the third band is the multiplier, which determines how many zeros to add.

What does the fourth band on a 4-band resistor indicate?

The fourth band on a 4-band resistor indicates the tolerance, which shows how much the actual resistance can vary from the nominal value. A gold band represents a 5% tolerance.

What is the resistance value of a resistor with a brown-black-brown-gold color code?

A brown-black-brown-gold resistor has a value of 100 ohms with a tolerance of ±5%.

How do 5-band resistors differ from 4-band resistors?

5-band resistors include an extra band for greater precision. The first three bands represent digits, the fourth is the multiplier, and the fifth indicates tolerance.

What does a tolerance of 1% on a resistor mean?

A 1% tolerance means the resistor's actual resistance can vary by 1% above or below its nominal value. For example, a 330-ohm resistor with 1% tolerance could range between 327 and 333 ohms.

What is the significance of measuring a resistor with a multimeter?

Measuring a resistor with a multimeter allows you to verify whether the actual resistance falls within the expected range and tolerance, confirming the resistor's accuracy.