Embibe Experts Solutions for Chapter: Current Electricity, Exercise 3: Level 3

A heating coil of resistance $100 \mathrm{\Omega }$ takes $100 \mathrm{s}$ to boil certain amount of water. If a similar heating coil is connected in series with the heating coil, then the time required to boil the water is $t_{\mathrm{s}}$, while $t_{\mathrm{p}}$ time is required to boil the same amount of water if the coils are connected in parallel. What will be $\frac{t_{\mathrm{s}}}{t_{\mathrm{p}}}$?

The unit of current element is $\underline{ }$
 

The resistors whose ratio is $1:2$ are connected in parallel, the ratio of power dissipated is:

The dimensions of a block are $1 \mathrm{cm}\times 1 \mathrm{cm}\times 100 \mathrm{cm}$. If the specific resistance of its material is $2\times {10}^{-7}$ $\mathrm{ohm}$$\times$$\mathrm{metre}$, then the resistance between the opposite rectangular faces is

When the temperature of a metallic resistor is increased, the product of its resistivity and conductivity:

A light bull is rated at $110 \mathrm{W}$ for a $220 \mathrm{V}$ supply. The resistance of the bulb is

What is the time $t$ taken by the capacitor in the given circuit to charge to $\frac{1}{\sqrt{2\pi }}$ of its full capacity?

There are two wires of the same material and lengths. The cross-sections of the wires are different. If the diameter of the first wire is double that of the second wire, then the specific resistance of the first wire will be