Here’s your video introduction to Lesson 2.3 of the Technician Class manual. The actual lesson is contained in the ARRL Ham Radio License Manual.

Archives
 October 2017
 June 2017
 May 2017
 April 2017
 March 2017
 February 2017
 January 2017
 December 2016
 November 2016
 October 2016
 September 2016
 August 2016
 July 2016
 June 2016
 May 2016
 April 2016
 March 2016
 February 2016
 January 2016
 December 2015
 November 2015
 October 2015
 September 2015
 August 2015
 July 2015
 June 2015
 May 2015
 April 2015
 March 2015
 February 2015
 January 2015
 December 2014
 November 2014
 October 2014
 September 2014
 August 2014
 July 2014
 June 2014
 May 2014
 April 2014
 March 2014
 February 2014
 January 2014
 December 2013
 November 2013
 October 2013
 September 2013
 July 2013
 June 2013
 May 2013
 April 2013
 March 2013
 February 2013
 January 2013
 November 2012
 October 2012
 September 2012
 August 2012
 July 2012
 June 2012
 May 2012
 April 2012
 March 2012
 February 2012
 January 2012
 December 2011
 November 2011
 October 2011
 September 2011
 August 2011
 July 2011
 June 2011
 May 2011
 April 2011
 March 2011
 February 2011
 January 2011
 November 2010
 October 2010
 September 2010
 August 2010
 July 2010
 June 2010
 May 2010
 April 2010
 March 2010

Meta
Hi Daniel, there are two ways of approaching this. First, let’s consider the current through one resistor without respect to the other. The current is the voltage divided by the resistance, or 40/1000, or 40 milliamps. Now, there are two such resistors, so the total current is 2 x 40 mA, or 80 mA. Second, let’s consider two resistors in parallel. The formula for two resistors in parallel is R – R1*R2 / (R1 + R2), or 1000*1000 / 2000, or 1,000,000/2,000 or 1000/2 or 500 ohms. Going back to ohm’s law, the current through this parallel combination is the voltage divided by the resistance, or 40/500, or 0.08 A or 80 mA. I hope that helps. 73!
First, I want to congrats on the quality of your videos. they have been nothing but helpful and insightful for the study of my exam. I am doing my exam in Canada. I don’t get why this proper the math is 1000/2= 500 then use that 500 in the formula??
Two resistors are connected in parallel and are connected across a 40 volt battery. If each resistor is 1000 ohms, the total current is:
A) 40 amperes
B) 80 amperes
C) 80 milliamperes
D) 40 milliamperes