If an electric current $I$ flows through a resistor $R$ in a circuit for time $t$,then the electrical energy $W$ consumed is given by:

An electric bulb is rated at $200 \ V - 100 \ W$. What is its resistance? If five such bulbs burn for $4 \ hours$, what is the total electrical energy consumed? Calculate the cost, if the rate is $50$ paise per unit.

$(a)$ Name an instrument that measures electric current in a circuit. Define the unit of electric current.
$(b)$ What do the following symbols mean in an electric circuit?
$(c)$ Draw a closed circuit diagram consisting of a $0.5\, m$ long nichrome wire $XY$,an ammeter,a voltmeter,four cells of $1.5\, V$ each,and a plug key.

Two wires $A$ and $B$ are of the same metal,have the same area of cross-section,and have their lengths in the ratio $2:1$. What will be the ratio of currents flowing through them respectively,when the same potential difference is applied across each of them?

$A$ house is fitted with $5$ tubes each of $40 \, W$. If all the tubes are lighted for $20$ hours and if the cost of electrical unit is ₹ $0.50$,the total cost of electricity consumed is (in ₹)

Two resistors are connected in series as shown in the diagram. $(i)$ What is the current through the $5 \, \Omega$ resistor? (ii) What is the current through $R$? (iii) What is the value of $R$? (iv) What is the value of $V$?