An electric circuit consisting of a $0.5 \mathrm{~m}$ long nichrome wire $\mathrm{XY}$, an ammeter, a voltmeter, four cells of $1.5 \mathrm{~V}$ each and a plug key was set up. (i) Draw a diagram of this electric circuit to study the relation between the potential difference maintained between the points ${ }^{\prime} \mathrm{X}^{\prime}$ and ${ }^{\prime} \mathrm{Y}^{\prime}$ and the electric current flowing through $\mathrm{XY}$. (ii) Following graph was plotted between $V$ and $I$ values: What would be the values of $\frac{V}{I}$ ratios when the potential difference is $0.8 \mathrm{~V}, 1.2 \mathrm{~V}$ and $1.6 \mathrm{~V}$ respectively $?$ What conclusion do you draw from these values? (iii) What is the resistance of the wire?"
This is the diagram of electric circuit to study the relation between the potential difference maintained between the points ${ }^{\prime} \mathrm{X}^{\prime}$ and ${ }^{\prime} \mathrm{Y}^{\prime}$ and the electric current flowing through $\mathrm{XY}$.
(ii)
When Potential, $\mathrm{V}=0.8 \mathrm{~V}$ then $, \frac{\mathrm{V}}{\mathrm{I}}=\frac{0.8}{0.3}=2.67$
At $V=1.2 \mathrm{~V},$ we have
$\frac{V}{I}=\frac{1.2}{0.45}=2.67$
At $V=1.6 \mathrm{~V},$ we have
$\frac{V}{I}=\frac{1.6}{0.6}=2.67$
As seen, ratio $\frac{V}{I}$ is constant in each case.
(iii)
The slope of the graph $\mathrm{V}$ vs. $I$ is equivalent to resistance.
Therefore, resistance of wire $X Y, R=2.67 \Omega$
Related Articles An electric room heater draws a current of 2.4 A from the $120 \mathrm{~V}$ supply line. What current will this room heater draw when connected to $240 \mathrm{~V}$ supply line?
An electric motor takes \( 5 \mathrm{~A} \) from a \( 220 \mathrm{~V} \) line. Determine the power of the motor and the energy consumed in \( 2 \mathrm{~h} \).
(a) What is the ratio of potential difference and current known as? (b) The values of potential difference $V$ applied across a resistor and the correponding values of current $I$ flowing in the resistor are given below: Potential difference, $V$ (in volts) : $\begin{array}{llllll}2.5 & 5.0 & 10.0 & 15.0 & 20.0 & 25.0\end{array}$Current, $I$ (in amperes) : $\begin{array}{llllll}0.1 & 0.2 & 0.40 & 0.60 & 0.80 & 1.0\end{array}$Plot a graph between $V$ and $I$, and calculate the resistance of the resistor.(c) Name the law which is illustrated by the above $V-I$ graph.(d) Write down the formula which states the relation between potential difference, current and resistance.(e) The potential difference between the terminals of an electric iron is $240 \mathrm{~V}$ and the current is $5.0 \mathrm{~A}$. What is the resistance of the electric iron?
The values of current (I) flowing through a given resistor of resistance (R), for the corresponding values of potential difference (V) across the resistor are as given below :V (Volts)0.51.01.52.02.53.04.05.0I (Amperes)0.10.20.30.40.50.60.81.0Plot a graph between current (I) and potential difference (V) and determine the resistance (R) of the resistor.
The p.d. across a $3 \Omega$ resistor is $6 \mathrm{~V}$. The current flowing in the resistor will be:(a) $\frac{1}{2} \mathrm{~A}$(b) $1 \mathrm{~A}$(c) $2 \mathrm{~A}$(d) $6 \mathrm{~A}$
In transferring \( 1.5 \mathrm{C} \) charge through a wire, \( 9 \mathrm{~J} \) of work is needed. Find the potential difference across the wire.
\( \mathrm{XYZW} \) is a rectangle. If \( \mathrm{XY}+\mathrm{YZ}=17 \) and \( \mathrm{XZ}+\mathrm{YW}=26 \), find \( \mathrm{XY} \) and \( \mathrm{YZ} .(\mathrm{XY}>\mathrm{YZ}) \).
In the given diagram of a simple pendulum, the time taken by the bob to move from \( \mathrm{X} \) to \( \mathrm{Z} \) is ' \( \mathrm{t}_{1} \) ' and from \( \mathrm{Z} \) to \( \mathrm{O} \) is \( ^{\prime} \mathrm{t}_{2}^{\prime} \). Find the time period of this simple pendulum."\n
Draw the perpendicular bisector of \( \overline{X Y} \) whose length is \( 10.3 \mathrm{~cm} \).(a) Take any point \( \mathrm{P} \) on the bisector drawn. Examine whether \( \mathrm{PX}=\mathrm{PY} \).(b) If \( \mathrm{M} \) is the mid point of \( \overline{\mathrm{XY}} \), what can you say about the lengths \( \mathrm{MX} \) and \( \mathrm{XY} \) ?
An electrical appliance has a resistance of $25 \Omega$. When this electrical appliance is connected to a $230 \mathrm{~V}$ supply line, the current passing through it will be:(a) $0.92 \mathrm{~A}$(b) $2.9 \mathrm{~A}$(c) $9.2 \mathrm{~A}$(d) $92 \mathrm{~A}$
Let \( \overline{\mathrm{PQ}} \) be the perpendicular to the line segment \( \overline{\mathrm{XY}} \). Let \( \overline{\mathrm{PQ}} \) and \( \overline{\mathrm{XY}} \) intersect in the point \( \mathrm{A} \). What is the measure of \( \angle \mathrm{PAY} \) ?
In \( \triangle \mathrm{ABC}, \mathrm{M} \) and \( \mathrm{N} \) are points of \( \mathrm{AB} \) and \( \mathrm{AC} \) respectively and \( \mathrm{MN} \| \mathrm{BC} \). If \( \mathrm{AM}=x \), \( \mathrm{MB}=x-2, \mathrm{AN}=x+2 \) and \( \mathrm{NC}=x-1 \), find the value of \( x \).
The weights of 8 students in a class were measured in kgs and the results are as follows: \( 45,50, \) \( 49,39,52,47,41, \) and 49 I) What is the weight of the heaviest student?II) What is the weight of the leanest student?III) What is the mean weight of the class? IV) How many students are there above the mean weight?A) \( I=52 \mathrm{kgs}, \mathrm{II}=41 \mathrm{kgs}, \mathrm{III}=46 \mathrm{kgs}, \mathrm{IV}=5 \)B) \( I=52 \mathrm{kgs}, \mathrm{II}=39 \mathrm{kgs}, \mathrm{III}=46.5 \mathrm{kgs}, \mathrm{IV}=5 \)C) \( 1=52 \mathrm{kgs}, \mathrm{II}=39 \mathrm{kgs}, \mathrm{III}=47 \mathrm{kgs}, \mathrm{IV}=4 \)D) \( \mathrm{I}=52 \mathrm{kgs}, \mathrm{II}=39 \mathrm{kgs}, \mathrm{III}=47 \mathrm{kgs}, \mathrm{IV}=5 \)
In \( \Delta \mathrm{XYZ}, \mathrm{S} \) and \( \mathrm{T} \) are points of \( \mathrm{XY} \) and \( \mathrm{XZ} \) respectively and ST \( \| \mathrm{YZ} \). If \( \mathrm{XS}=4 \mathrm{~cm} \), \( \mathrm{XT}=8 \mathrm{~cm}, \mathrm{SY}=x-4 \mathrm{~cm} \) and \( \mathrm{TZ}=3 x-19 \mathrm{~cm} \) find the value of \( x \).
How much work is done in moving a charge of $2 \mathrm{C}$ across two points having a potential difference of $12 \mathrm{~V}$ ?
Kickstart Your Career
Get certified by completing the course
Get Started