Induced potential, transformers and the National Grid (physics only) (HT only) common mistakes

Common mistakes

• National Grid transformer reasoning: avoid AC and DC

  Treating AC and DC as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a bar magnet and plotting compass practical and the objective to describe how a potential difference is induced across a conductor when the conductor moves relative to a magnetic field.

• National Grid transformer reasoning: avoid magnetic field...

  Treating magnetic field direction and force direction as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a steel core electromagnet demonstration and the objective to describe how a potential difference is induced when there is a change in the magnetic field around a conductor.

• National Grid transformer reasoning: avoid magnetic field...

  Treating magnetic field direction and force direction as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a current-carrying wire between magnetic poles and the objective to state that a current is induced if the conductor is part of a complete circuit.

• National Grid transformer reasoning: avoid motors and generators

  Treating motors and generators as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a loudspeaker coil moving in a magnetic field and the objective to describe induced potential difference and induced current as the generator effect.

• National Grid transformer reasoning: avoid induced and supplied...

  Treating induced and supplied current as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to an alternator producing an AC output trace and the objective to state that an induced current generates a magnetic field that opposes the original change.

• National Grid transformer reasoning: avoid magnetic field...

  Treating magnetic field direction and force direction as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a dynamo producing a DC output trace and the objective to explain that the original change may be the movement of the conductor or the change in magnetic field.

• National Grid transformer reasoning: avoid AC and DC

  Treating AC and DC as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a moving-coil microphone investigation and the objective to recall the factors that affect the size of the induced potential difference or induced current.

• National Grid transformer reasoning: avoid AC and DC

  Treating AC and DC as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a step-up transformer on the National Grid and the objective to recall the factors that affect the direction of the induced potential difference or induced current.

• National Grid transformer reasoning: avoid motors and generators

  Treating motors and generators as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a step-down transformer for a low-voltage device and the objective to apply the principles of the generator effect in a given context.

• National Grid transformer reasoning: avoid electromagnets and...

  Treating electromagnets and permanent magnets as interchangeable when answering about National Grid transformer reasoning.

  Fix itInstead, identify the exact Unit 4.7 idea in Induced potential (HT only), then explain how it links to a student comparing motor and generator effects and the objective to distinguish induced current from supplied current in electromagnetic devices.