Mathematical and Physical Journal
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Problem P. 4477. (November 2012)

P. 4477. A small incandescent lamp, rated at 2 W/20 V, is to be operated with the aid of a 100-ohm variable resistor and a voltage supply of voltage 40 V. How can this be done?

(4 pont)

Deadline expired on December 10, 2012.

Sorry, the solution is available only in Hungarian. Google translation

Megoldásvázlat. Az izzó ellenállása 200 ohm. A teljes tolóellenállásra kapcsolva a 40 V-os forrást, a tolóérintkező \(\displaystyle 56\%\)-os helyzeténél a rá kapcsolt kis izzóra éppen 20 V jut.


142 students sent a solution.
4 points:113 students.
3 points:11 students.
2 points:3 students.
1 point:7 students.
0 point:8 students.

Problems in Physics of KöMaL, November 2012