The resistance of the series combination of two resistance is S. When they are joined in parallel the total resistance is P. If S = nP, then the minimum possible value of n is :

(1) 4

(2) 3

(3) 2

(4) 1

A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be 

(1) 99995

(2) 9995

(3) 10³

(4) 10⁵

Which of the adjoining graphs represents ohmic resistance ?

(1)

(2)

(3)

(4)

Variation of current passing through a conductor with the voltage applied across its ends varies is shown in the diagram below. If the resistance \((R)\) is determined at points \(A\), \(B\), \(C\) and \(D\), we will find that:

The voltage V and current I graph for a conductor at two different temperatures T₁ and T₂ are shown in the figure. The relation between T₁ and T₂ is :

(1) T₁ > T₂

(2) $T_1\approx T_2$

(3) T₁ = T₂

(4) T₁ < T₂

From the graph between current \(I\) and voltage \(V\) shown below, identify the portion corresponding to negative resistance 

1. \(AB\)
2. \(BC\)
3. \(CD\)
4. \(DE\)

I-V characteristic of a copper wire of length L and area of cross-section A is shown in figure. The slope of the curve becomes :

(1) More if the experiment is performed at higher temperature

(2) More if a wire of steel of same dimension is used

(3) More if the length of the wire is increased

(4) Less if the length of the wire is increased

E denotes electric field in a uniform conductor, I corresponding current through it, V_d drifts velocity of electrons and P denotes thermal power produced in the conductor, then which of the following graph is incorrect :

(1)

(2)

(3)

(4)

The two ends of a uniform conductor are joined to a cell of e.m.f. E and some internal resistance. Starting from the midpoint P of the conductor, we move in the direction of current and return to P. The potential V at every point on the path is plotted against the distance covered (x). Which of the following graphs best represents the resulting curve

(1)

(2)

(3)

(4)

The resistance R_t of a conductor varies with temperature t as shown in the figure. If the variation is represented by $R_t=R_0\left[1+\alpha t+\beta t^2\right]$, then 

(1) α and β are both negative

(2) α and β are both positive

(3) α is positive and β is negative

(4) α is negative and β are positive