Embibe Experts Solutions for Exercise 3: EXERCISE

A $1500 \mathrm{W}$ radiant heater is constructed to operate at $115 \mathrm{V}$.

(a) What will be the current in the heater?

(b) What is the resistance of the heating coil?

(c) How many kilocalories are generated in one hour by the heater?

Given three resistors of resistances $R_1,R_2$ and $R_3$, how should they be connected to

(a) maximize

(b) minimize the equivalent resistance?

A wire of resistance $R$ is cut into $n$ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be

A copper wire of resistance $R$ is cut into ten parts of equal length. Two pieces each are joined in series and then five such combination are joined in parallel. The new combination will have a resistance

When a resistance of $2 \mathrm{\Omega }$ is connected across the terminals of a cell, the current is $0.5$ amperes. When the resistance is increased to $5 \mathrm{ohm},$ the current is $0.25$ amperes. The internal resistance of the cell is