In which of the following devices, the eddy current effect is not used?
- induction furnace
- magnetic braking in train
- electromagnet
- electric heater
The Correct Option is D
Solution and Explanation
To solve the question of identifying which device does not utilize the eddy current effect, we need to understand what eddy currents are and how they are applied in various devices.
Eddy Currents Explanation: Eddy currents are loops of electric current induced within conductors by a changing magnetic field in the conductor. They can lead to significant heat production due to the resistance of the conducting material. These currents are used in several devices for their heating effects or electromagnetic properties.
Let's analyze each option:
- Induction Furnace: This type of furnace uses eddy currents to heat metals. The alternating magnetic field induces currents in the metal, which due to the metal's resistance, produces heat. \text{Induction Furnace = Uses Eddy Currents}
- Magnetic Braking in Trains: Eddy currents are used in magnetic braking systems where a magnetic field induces eddy currents in the train's wheels or tracks. These currents oppose the motion due to Lenz's law, providing a braking force. \text{Magnetic Braking = Uses Eddy Currents}
- Electromagnet: While electromagnets utilize electric currents to produce a magnetic field, the magnetic field itself can induce eddy currents in nearby conductors. While this is not the primary purpose, eddy currents can occur if conditions permit. \text{Electromagnet = Eddy Currents Possible}
- Electric Heater: This primarily works on the principle of resistive heating (Joule heating) and not on eddy currents. It uses the resistance of a wire to convert electric energy into heat without any magnetic induction. \text{Electric Heater = Does Not Use Eddy Currents}
Conclusion: Based on the above analysis, the device that does not use the eddy current effect is the electric heater. It relies on converting electrical energy directly into heat without the assistance of changing magnetic fields and induced currents.
Top NEET Physics Questions
- The time constant of C-R circuit is
- The correct Boolean operation represented by the circuit diagram drawn is :
- The driver of a car travelling with speed $30\, m/sec$ towards a hill sounds a horn of frequency $600\, Hz.$ If the velocity of sound in air is $330\, m/s,$ the frequency of reflected sound as heard by driver is
- Two simple harmonic motions of angular frequency 100 and 1000 rad $s^1$ have the same displacement amplitude. The ratio of their maximum acceleration is
- In an ac circuit , an alternating voltage $e = 200 \sqrt2 \,sin \,100\, t$ volts is connected to a capacitor of capacitance $1 \,\mu \,F$. The rms value of the current in the circuit is :
Top NEET Questions
- A $100.0\, mL$ dilute solution of $Ag ^{+}$is electrolysed for $15.0$ minutes with a current of $1.25 \,mA$ and the silver is removed completely. What was the initial $\left[ Ag ^{+}\right]$?
- The time constant of C-R circuit is
- The chronological order of human evolution from early to the recent is
- The correct Boolean operation represented by the circuit diagram drawn is :
- The driver of a car travelling with speed $30\, m/sec$ towards a hill sounds a horn of frequency $600\, Hz.$ If the velocity of sound in air is $330\, m/s,$ the frequency of reflected sound as heard by driver is