Question:
A hot electric iron has a resistance of $80\, \Omega$ and is used on a $200\, V$ source. The electrical energy spent, if it is used for $2\, hr$, will be :
A hot electric iron has a resistance of $80\, \Omega$ and is used on a $200\, V$ source. The electrical energy spent, if it is used for $2\, hr$, will be :
Updated On: Jul 5, 2022
- 8000 Wh
- 2000 Wh
- 1000 Wh
- 800 Wh
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The Correct Option is C
Solution and Explanation
Here : Resistance $R =80 \Omega$
Voltage $V =200\, V$
Time $t =2\, hr$
Voltage $V=200\, V$
The relation of power is given by
$P=\frac{V^{2}}{R}=\frac{(200)^{2}}{80}=500\, W$
Hence, energy spent is given by
=power $\times$ time
$=500 \times 2=1000\, Wh$
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Concepts Used:
Electromagnetic Induction
Electromagnetic Induction is a current produced by the voltage production due to a changing magnetic field. This happens in one of the two conditions:-
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- When the conductor constantly moves in a stationary field.
Formula:
The electromagnetic induction is mathematically represented as:-
e=N × d∅.dt
Where
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- N = number of turns in the coil
- Φ = Magnetic flux (This is the amount of magnetic field present on the surface)
- t = time
Applications of Electromagnetic Induction
- Electromagnetic induction in AC generator
- Electrical Transformers
- Magnetic Flow Meter