14 Matching Annotations
  1. Jun 2023
    1. Example 1: If a 1000-Ω resistor is connected in parallel with a3000-Ω resistor, what is the total or equivalent resistance? Alsocalculate total current and individual currents, as well as thetotal and individual dissipated powers.R R RR R1000 30001000 30003, 000, 0004000 750total1 21 2= ×+ = Ω × ΩΩ + Ω = ΩΩ = ΩTo find how much current flows through each resistor, applyOhm’s law:I VRI VR12 V1000 0.012 A 12 mA12 V3000 0.004 A 4 mA111222= = Ω = == = Ω = =These individual currents add up to the total input current:Iin = I1 + I2 = 12 mA + 4 mA = 16 mAThis statement is referred to as Kirchhoff’s current law. Withthis law, and Ohm’s law, you come up with the current divider

      Great intro problem to Kirchhoff's current law

      Current divider notes as well!

  2. Jan 2023
  3. Dec 2022
  4. Oct 2022
    1. good enough to clearly image the internal workings of a de-capped integrated circuit

      Detailed enough to visualise de-capped IC layout

  5. Jun 2021
  6. Apr 2021
    1. A falsey return value from #validate will deviate the flow and go straight to End.fail_fast.

      Similar to: How, in Rails, aborting a before_action causes all later ones to be skipped.

  7. Nov 2020
    1. Important caveat: in the combined expression, if the middle command has a non-zero exit status, then both the middle and the rightmost command end up getting executed.

      I don't think that is surprising, is it? Since && and || have the same order of precedence. So I think this is more of a clarification than a caveat.

      I think this is just because:

      a && b || c is equivalent to: (a && b) || c (so of course c gets evaluated if (a && b) is false (that if either a or b is false).

      I think they just mean, in this case:

      bedmap && mv || fail

      if mv fails, then fail still gets executed.

      Easier to see with a simpler example:

      ⟫ true && false || echo 'fail'
      ⟫ false && true || echo 'fail'

      Better example/explanation here: https://hyp.is/-foxmCVXEeuhnLM-le_R4w/mywiki.wooledge.org/BashPitfalls

      The caveat/mistake here is if you treat it / think that it is equivalent to if a then b else c. That is not the case if b has any chance of failing.

    1. The potential problem: if second_task fails, third_task will not run, and execution will continue to the next line of code - next_task, in this example. This may be exactly the behavior you want. Alternatively, you may be intending that if second_task fails, the script should immediately exit with its error code. In this case, the best choice is to use a block - i.e., curly braces: first_task && { second_task third_task } next_task Because we are using the -e option, if second_task fails, the script immediately exits.
    2. When people write COND && COMMAND, typically they mean "if COND succeeds (or is boolean true), then execute COMMAND. Regardless, proceed to the next line of the script." It's a very convenient shorthand for a full "if/then/fi" clause.
  8. Jul 2020
  9. May 2020
    1. For instance, cor does not distribute over cand: compare (A cand B) cor C with (A cor C) cand (B cor C); in the case ¬A ∧ C , the second expression requires B to be defined, the first one does not
  10. Dec 2019
    1. this system enables longer duration production, and could be readily applied to burdensome or toxic products not readily produced in bacteria
  11. Jul 2018
    1. Figure 3: Motor system with flip switch and potentiometer

      Please add a wiring diagram that would allow someone to reproduce this circuit.