Lenz’s Law

Lenz’s Law MDCAT MCQs with answers

18 past paper MCQs on Lenz’s Law, from the Electromagnetic Induction unit of MDCAT Physics. The year each question appeared is shown where known; tap “Show answer” for the correct option and a short solution.

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1.The working principle of the magnetic levitation train is: (MDCAT 2022)

  1. Faraday's law
  2. Planck's law
  3. Ohm's law
  4. Lenz's law
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Correct answer: (d) Lenz's law

The induced currents oppose the approaching magnets, and that repulsion is Lenz's law at work.

2.The statement that the induced current will flow in such a direction as to oppose the cause that produces it is: (MDCAT 2024)

  1. Ampere's law
  2. Faraday's law
  3. Lenz's law
  4. Joule's law
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Correct answer: (c) Lenz's law

That is Lenz's law, and it is the conservation of energy applied to induction.

3.A metallic circular ring is suspended by a string in a vertical plane. When a magnet is brought towards the ring, the ring will: (UHS MDCAT 2017)

  1. remain stationary
  2. get displaced away from the magnet
  3. get displaced towards the magnet
  4. nothing can be said
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Correct answer: (b) get displaced away from the magnet

By Lenz law the induced current opposes the approach, so the ring is repelled and swings away.

4.A loop moves toward a stationary magnet. The induced current will: (UHS MDCAT 2025)

  1. enhance the motion
  2. try to stop the approach
  3. become zero
  4. become alternating
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Correct answer: (b) try to stop the approach

By Lenz’s law the induced current opposes the change that made it, so it opposes the approach.

5.According to Lenz's Law, the direction of induced current in a conductor is such that it: (KMU MDCAT 2025)

  1. Opposes the change in magnetic flux
  2. Enhances the change in magnetic flux
  3. Is perpendicular to the magnetic field
  4. Is parallel to the magnetic field
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Correct answer: (a) Opposes the change in magnetic flux

The induced current always sets up a flux that opposes the change producing it.

6.A conducting ring is placed near a current-carrying coil. As the current in the coil increases, the induced current in the ring flows: (SZABMU MDCAT 2025)

  1. In the direction of magnetic field
  2. To increases the magnetic flux
  3. To oppose increasing magnetic flux
  4. Randomly without a definite direction
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Correct answer: (c) To oppose increasing magnetic flux

By Lenz’s law the ring drives a current whose own flux opposes the rise.

7.160.The induced current will flow in such a direction so as to oppose the cause that produces it is statement of: (UHS MDCAT 2024)

  1. Ampere's Law
  2. Faraday's Law
  3. Lenz's Law
  4. Joule's Law
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Correct answer: (c) Lenz's Law

That is Lenz’s law.

8.The direction of induced current is determined by? (KMU MDCAT 2024)

  1. Ampere’s law
  2. Faraday’s law
  3. Lenz’s law
  4. Ohm’s law
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Correct answer: (c) Lenz’s law

Lenz’s law fixes the direction; Faraday’s law gives the size.

9.Lenz’s law is consistent with the (KMU MDCAT 2024)

  1. Ampere’s Law
  2. Faraday’s law
  3. Law of conservation of energy
  4. Ohm’s law
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Correct answer: (c) Law of conservation of energy

If the induced current helped the change, energy would be made from nothing.

10.Q.165 Working principal of magnetic levitation train is according to ? (UHS MDCAT 2023)

  1. Faraday law
  2. Max planks law
  3. Ohm law
  4. Lenz law
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Correct answer: (d) Lenz law

The induced currents oppose the approaching magnet, and the repulsion is what lifts the train.

11.Lenz’s law is also a statement of law of conservation of: (SZABMU MDCAT 2023)

  1. Charge
  2. Energy
  3. Momentum
  4. Mass
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Correct answer: (b) Energy

If the induced current helped the change, energy would be created out of nothing.

12.The Lenz's law is also statement of law of conservation of: (NUMS MDCAT 2023)

  1. Charge
  2. Mass
  3. Energy
  4. Pressure
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Correct answer: (c) Energy

If the induced current helped the change, energy would be made from nothing.

13.The negative sign in Lenz’s law indicates that the induced emf opposes the rate of change of: (PMC MDCAT 2022)

  1. Electric flux
  2. Magentic flux
  3. Electric field
  4. Magentic field
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Correct answer: (b) Magentic flux

The induced emf opposes the change of flux that produced it.

14.The Lenz’s law is used to find out the direction of (PMC MDCAT 2022)

  1. Current induced in circuit
  2. Potential energy
  3. Magnetic field
  4. Force
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Correct answer: (a) Current induced in circuit

Lenz’s law fixes the direction of the induced current.

15.Q.69 Lenz's law is based on the law of conservation of: (NUMS MDCAT 2022)

  1. Mass
  2. Energy
  3. Charge
  4. Momentum
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Correct answer: (b) Energy

If the induced current helped the change, energy would be created out of nothing.

16.The Lenz’s law refers to: (PMC Practice 2021)

  1. Induced current
  2. Induced potential
  3. Motional emf
  4. All of these
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Correct answer: (d) All of these

Lenz’s law fixes the direction of the induced current, and so of the emf that drives it.

17.Lenz’s law in electromagnetic induction is the direct consequence of the principle of conservation of: (UHS MDCAT 2018)

  1. Energy
  2. Charge
  3. Momentum
  4. Mass
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Correct answer: (a) Energy

If the induced current helped the change, energy would be made from nothing.

18.A metallic circular ring is suspended by a string and is kept in a vertical plane. When a magnet is approached towards the ring, then it will: (UHS MDCAT 2017)

  1. Remain stationary
  2. Get displaced away from the magnet
  3. Get displaced towards the magnet
  4. Nothing can be said
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Correct answer: (b) Get displaced away from the magnet

The changing flux induces a current in the ring whose field opposes the magnet, so the ring is pushed away.

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