Answer
Verified
36.6k+ views
Hint: The above problem is based on the electric power. The electric power depends on the current, voltage and resistance of the electric device. The electric power can be calculated by using the two variables form the current, voltage and resistance.
Solution
The formula to calculate the power of the iron is given as,
$P = V \cdot I$
Substitute $200\;{\text{V}}$ for $V$ and $4\;{\text{A}}$ for $I$ in the above expression to find the power rating of the iron.
$P = \left( {200\;{\text{V}}} \right)\left( {4\;{\text{A}}} \right)$
$P = 800\;{\text{W}}$
Thus, the power rating of the iron is $800\;{\text{W}}$and the option (A) is the correct answer.
Additional Information: The voltage difference is necessary for the flow of charge in the electric circuit. The current is the same as the flow of charge in unit time. The resistance is the property of the material that opposes the flow of the charge in the electric circuit. Mathematically, it is the same as the ratio of the voltage to current. The resistance varies with the cross sectional area of the wire and length of the wire.
The electric power may be active power, reactive power or apparent power.
Note: The above problem can also be solved by using the other formula of electric power. The electric power can also be calculated by using the formula either $P = {I^2}R$ or $P = \dfrac{{{V^2}}}{R}$. The resistance can be found by using the formula $R = \dfrac{V}{I}$. This formula of the resistance is only valid for the Ohmic materials.
Solution
The formula to calculate the power of the iron is given as,
$P = V \cdot I$
Substitute $200\;{\text{V}}$ for $V$ and $4\;{\text{A}}$ for $I$ in the above expression to find the power rating of the iron.
$P = \left( {200\;{\text{V}}} \right)\left( {4\;{\text{A}}} \right)$
$P = 800\;{\text{W}}$
Thus, the power rating of the iron is $800\;{\text{W}}$and the option (A) is the correct answer.
Additional Information: The voltage difference is necessary for the flow of charge in the electric circuit. The current is the same as the flow of charge in unit time. The resistance is the property of the material that opposes the flow of the charge in the electric circuit. Mathematically, it is the same as the ratio of the voltage to current. The resistance varies with the cross sectional area of the wire and length of the wire.
The electric power may be active power, reactive power or apparent power.
Note: The above problem can also be solved by using the other formula of electric power. The electric power can also be calculated by using the formula either $P = {I^2}R$ or $P = \dfrac{{{V^2}}}{R}$. The resistance can be found by using the formula $R = \dfrac{V}{I}$. This formula of the resistance is only valid for the Ohmic materials.
Recently Updated Pages
To get a maximum current in an external resistance class 1 physics JEE_Main
f a body travels with constant acceleration which of class 1 physics JEE_Main
A hollow sphere of mass M and radius R is rotating class 1 physics JEE_Main
If the beams of electrons and protons move parallel class 1 physics JEE_Main
Two radioactive nuclei P and Q in a given sample decay class 1 physics JEE_Main
If a wire of resistance R is stretched to double of class 12 physics JEE_Main
Other Pages
The nitride ion in lithium nitride is composed of A class 11 chemistry JEE_Main
The mole fraction of the solute in a 1 molal aqueous class 11 chemistry JEE_Main
An electric bulb has a power of 500W Express it in class 11 physics JEE_Main
Normality of 03 M phosphorus acid H3PO3 is A 05 B 06 class 11 chemistry JEE_Main
A closed organ pipe and an open organ pipe are tuned class 11 physics JEE_Main
For an electromagnet the core should have A High retentivity class 12 physics JEE_Main