Chapter 14: Problem 43
Kirchhoff's second law is based on the law of conservation of (A) Momentum (B) Charge (C) Energy (D) Sum of mass and energy
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 14: Problem 43
Kirchhoff's second law is based on the law of conservation of (A) Momentum (B) Charge (C) Energy (D) Sum of mass and energy
All the tools & learning materials you need for study success - in one app.
Get started for free
Two conductors have the same resistance at \(0^{\circ} \mathrm{C}\) but their temperature coefficients of resistance are \(\alpha_{1}\) and \(\alpha_{2} .\) The respective temperature coefficients of their series and parallel combinations are nearly (A) \(\frac{\alpha_{1}+\alpha_{2}}{2}, \alpha_{1}+\alpha_{2}\) (B) \(\alpha_{1}+\alpha_{2}, \frac{\alpha_{1}+\alpha_{2}}{2}\) (C) \(\alpha_{1}+\alpha_{2}, \frac{\alpha_{1} \alpha_{2}}{\alpha_{1}+\alpha_{2}}\) (D) \(\frac{\alpha_{1}+\alpha_{2}}{2}, \frac{\alpha_{1}+\alpha_{2}}{2}\)
Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage difference are \(3 \%\) each, then error in the value of resistance of the wire is (A) \(6 \%\) (B) Zero (C) \(1 \%\) (D) \(3 \%\)
Two cells with the same EMF \(E\) and different internal resistances \(r_{1}\) and \(r_{2}\) are connected in series to an external resistance \(R\). The value of \(R\) for the potential difference across the first cell to be zero is (A) \(\sqrt{r_{1} r_{2}}\) (B) \(r_{1}+r_{2}\) (C) \(r_{1}-r_{2}\) (D) \(\frac{r_{1}+r_{2}}{2}\)
Figure \(14.47\) shows the circuit of a potentiometer. The length of the potentiometer wire \(A B\) is \(50 \mathrm{~cm}\). The EMF \(E_{1}\) of the battery is \(4 \mathrm{~V}\), having negligible internal resistance. Value of \(R_{1}\) and \(R_{2}\) are \(15 \Omega\) and \(5 \Omega\), respectively. When both the keys are open, the null point is obtained at a distance of \(31.25 \mathrm{~cm}\) from \(A\), but when both the keys are closed, the balance length reduces to \(5 \mathrm{~cm}\) only. Given \(R_{A B}=10 \Omega\) The balance length when key \(K_{1}\) is open and \(K_{2}\) is closed is given by (A) \(10.5 \mathrm{~cm}\) (B) \(11.5 \mathrm{~cm}\) (C) \(12.5 \mathrm{~cm}\) (D) \(25 \mathrm{~cm}\)
A potentiometer is a device used for measuring EMF and internal resistance of a cell. It consists of two circuits, one is main circuit in which there is a cell of given emf \(\varepsilon^{\prime}\) and given resistance \(R\) which is connected across a wire of length \(100 \mathrm{~cm}\) and having resistance \(r\) and another circuit having unknown EMF \(\varepsilon\) and galvanometer. For a given potentiometer, if \(\varepsilon^{\prime}=30 \mathrm{~V}, r=1 \Omega\), and resistance \(R\) varies with time \(t\) given by \(R=2 t\). The jockey can move on wire with constant velocity \(10 \mathrm{~cm} / \mathrm{s}\) and switch \(S\) is closed at \(t=0\)If jockey starts moving from \(A\) at \(t=0\) and balancing point found at \(t=1 \mathrm{~s}\) then the value of \(\varepsilon\) is (A) \(1 \mathrm{~V}\) (B) \(2 \mathrm{~V}\) (C) \(3 \mathrm{C}\) (D) \(4 \mathrm{~V}\)
What do you think about this solution?
We value your feedback to improve our textbook solutions.