Current ElectricityElectrical Resistance (KVPY StreamSA (Class 11) Physics): Questions 1  2 of 2
Get 1 year subscription: Access detailed explanations (illustrated with images and videos) to 252 questions. Access all new questions we will add tracking exampattern and syllabus changes. View Sample Explanation or View Features.
Rs. 200.00 or
Question number: 1
» Current Electricity » Electrical Resistance
Write in Short
Consider the two circuits P and Q, shown below, which are used 20 measure the unknown resistance R.
In each case, the resistance is estimated by using Ohm’s law , Where V and I are the readings of the voltmeters and the ammeters respectively. The internal resistances of voltmeter and ammeter are R _{V} and R _{A}, such that R _{A} < < R < < R _{V}.
The internal resistance of the battery may be ignored. The absolute error in the estimate of the resistance is denoted by δ R = R  Rest .
(a) Express δ R _{P} in terms of the given resistance values
(b) Express δ R _{Q} in terms of the given resistance values
(c) For what value of R will δ R _{P } ≈ δ R _{Q}
Question number: 2
» Current Electricity » Electrical Resistance
Appeared in Year: 2011
Question
A cylindrical copper rod has length L and resistance R. If it is melted and formed into another rod of length 2L, than the resistance will be
Choices
Choice (4)  Response  

a.  8R 

b.  R 

c.  4R 

d.  2R 
