Embibe Experts Solutions for Chapter: Current Electricity, Exercise 1: KEAM 2020

The contribution to the total current in a semiconductor, due to electrons and holes are $0.75$ and $0.25$ respectively. The drift velocity of electrons is $\frac{3}{2}$ times that of holes at this temperature. Then the ratio between electron concentration and hole concentration is

A steady current flows in a metallic conductor of non-uniform cross section. The quantity/quantities that remains/remain constant along the length of the conductor is/are

Find the voltage and current passing through the resistor $R_2$ shown in the following circuit

In a platinum resistance thermometer, the resistances of the wire at ice point and steam point are of $4\mathrm{\Omega }$ and $4.25\mathrm{\Omega }$ respectively. When the thermometer is kept in a hot water bath, whose temperature is not known, the resistance of the wire is found to be $4.5\mathrm{\Omega }.$ The temperature of the hot water bath is

The resistor $R_1=3 \Omega$ and$R_2=1 \Omega$ are connected in parallel to a $20 \mathrm{V}$ battery. Find the heat developed in the resistor $R_1$ in one minute

Internal resistance of a cell is independent of

Six cells, each of emf $5\mathrm{V}$ and internal resistance $0.1\mathrm{\Omega }$ are connected as shown in Figure. The reading of the ideal voltmeter $\mathrm{V}$ is

A parallel plate capacitor (of capacitance $C)$ with circular plates of radius $r_0$ located at position $\pm \alpha ,$ is connected in series with a resistor $R$ and is charged by a battery of voltage $V.$ Consider a circular loop $L$ of radius $\underset{¯}{r_0}$ parallel to the capacitor plates is located at $\overline{2}$ the center. Which of the following statements is correct ?