KöMaL - Középiskolai Matematikai és Fizikai Lapok
Sign In
Sign Up
 Magyar
Information
Contest
Journal
Articles

 

Problem P. 4335. (March 2011)

P. 4335. The electromotive force of the voltage supply in the circuit, shown in the figure, is U0=9 V and its internal resistance Rb is unknown. The resistances of the meters and the resistor are also unknown. When the switch is closed then the measured current increases to twice of the previous value, and the reading on the voltmeter decreases to half of the original value.

a) By what factor is the resistance of the voltmeter greater than that of the resistor?

b) What are the readings on the voltmeter before and after closing the switch?

(4 pont)

Deadline expired on 11 April 2011.


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

Megoldás. \(\displaystyle a)\) 3-szorosa.

\(\displaystyle b)\) Nyitott kapcsolónál 6 V-ot, zárt kapcsolónál 3 V-ot mér a voltmérő.


Statistics:

79 students sent a solution.
4 points:59 students.
3 points:8 students.
2 points:7 students.
1 point:4 students.
0 point:1 student.

Our web pages are supported by:   Ericsson   Cognex   Emberi Erőforrás Támogatáskezelő   Emberi Erőforrások Minisztériuma   Nemzeti Tehetség Program    
MTA Energiatudományi Kutatóközpont   MTA Wigner Fizikai Kutatóközpont     Nemzeti
Kulturális Alap   ELTE   Morgan Stanley