Everything Science Grade 11

19.3 CHAPTER 19. ELECTRIC CIRCUITS

R 1 =3 Ω

R 2 =10 Ω

R 3 =5 Ω

9 V

A B

D C

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The resistors are in series, therefore:

Rs = R 1 + R 2 + R 3

= 3Ω + 10Ω + 5Ω

= 18Ω

See video: VPmiy at http://www.everythingscience.co.za

Example 2: Equivalent series resistance I

QUESTION

Two 10 kΩ resistors are connectedin series. Calculate the equivalent resistance.

SOLUTION

Step 1 : Determine how to approach the problem

Since the resistors are inseries we can use:

Rs= R 1 + R 2

Step 2 : Solve the problem

Rs = R 1 + R 2

= 10kΩ + 10kΩ

= 20kΩ

Step 3 : Write the final answer

The equivalent resistance of two 10 kΩ resistors connected in series is 20 kΩ.