Pankaj Bhatt Solutions for Chapter: Electrical Power and Household Circuits, Exercise 1: QUESTIONS

An electric kettle is marked $1000 \mathrm{W}, 220 \mathrm{V}$. What is the resistance of its filament and how much is the current passing through it? 

Three equal resistors when connected in series consume $10 \mathrm{W}$ of power from a battery. Calculate the power consumed if these resistors are connected in parallel to the same battery. 

The figure shows three resistors of $4 \mathrm{\Omega }, 6 \mathrm{\Omega }, 8 \mathrm{\Omega }$ are connected to a battery of $6 \mathrm{V}$. What is the net resistance of the circuit? How much is the current drawn from the cell and what is the power consumed by $6 \mathrm{\Omega }$ resistor?

Calculate the net resistance of the circuit given in the figure. If internal resistance of the $6 \mathrm{V}$ battery is $2 \mathrm{\Omega }$, calculate the heat produced by $4 \mathrm{\Omega }$ resistor in $10 \mathrm{s}$.

In a house, three tube lights each of $40 \mathrm{W}$, two electric bulbs each of $100 \mathrm{W}$ and a fridge of $500 \mathrm{W}$ run six hours daily. What is the consumption of electric units in the house in a month? Calculate the cost of electricity at $\mathrm{Rs}.2$per unit.

The filament of a room heater of $1000 \mathrm{W}$ at $220 \mathrm{V}$is cut into three equal pieces. Now one of these pieces is rearranged in the heater. Calculate the new electrical power of the heater if connected to $220 \mathrm{V}$ again?

$5 \mathrm{A}$ of current flows through a resistor of $10 \mathrm{\Omega }$ for $20 \mathrm{s}$. Calculate the heat produced by each free electron passing through the resistor.

Two electric bulbs each are marked $100 \mathrm{W}, 250 \mathrm{V}$ are connected in series to a $250 \mathrm{V}$ dc supply. What is the resistance of each bulb? How much power is consumed by each bulb in the circuit?