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PHYSICS, M7 2023 HSC 6 MC

An electron would produce an electromagnetic wave when it is

  1. stationary.
  2. in a stable hydrogen atom.
  3. moving at a constant velocity.
  4. moving at a constant speed in a circular path.
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\(D\)

Show Worked Solution

→ Maxwell predicted that an accelerating charge will produce an electromagnetic wave.

→ As the electron moves at a constant speed in a circular path it must be experiencing an acceleration.

\(\Rightarrow D\)

♦ Mean mark 52%.

PHYSICS, M7 EQ-Bank 1 MC

In which of the following areas of physics did James Clerk Maxwell NOT contribute to our understanding?

  1. The unification of electricity and magnetism through equations.
  2. Predicting light is a form of electromagnetic radiation.
  3. Predicting the velocity of electromagnetic waves
  4. Validating the existence of electromagnetic waves
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`D`

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→ Maxwell’s contributions to our understanding of electromagnetism were only theoretical.

→ Maxwell used equations to predict the existence and properties of electromagnetic waves, however, never experimentally validated their existence.

`=>D`

PHYSICS, M7 2019 HSC 25

The diagram shows a model of electromagnetic waves.
 


 

Relate this model to predictions made by Maxwell.   (4 marks)

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→ The diagram shows alternating electric and magnetic fields oscillating perpendicular to each other. This relates to Maxwell’s prediction of mutual inductance; that a changing electric field induces a changing magnetic field and vice versa.

→ The diagram shows the electromagnetic wave propagating with velocity `v `. This relates to Maxwell’s prediction of a range of waves with different wavelengths, all travelling at the same speed where `c=(1)/(sqrt(mu_(0)epsilon_(0)))`.

→ The diagram also shows an electromagnetic wave emanating from an oscillating charge. This is consistent with Maxwell’s prediction that an oscillating electric charge produces a changing electric field, which in turn produces a changing magnetic field. These fields continue to mutually induce each other, producing an electromagnetic wave.

Show Worked Solution

→ The diagram shows alternating electric and magnetic fields oscillating perpendicular to each other. This relates to Maxwell’s prediction of mutual inductance; that a changing electric field induces a changing magnetic field and vice versa.

→ The diagram shows the electromagnetic wave propagating with velocity `v `. This relates to Maxwell’s prediction of a range of waves with different wavelengths, all travelling at the same speed where `c=(1)/(sqrt(mu_(0)epsilon_(0)))`.

→ The diagram also shows an electromagnetic wave emanating from an oscillating charge. This is consistent with Maxwell’s prediction that an oscillating electric charge produces a changing electric field, which in turn produces a changing magnetic field. These fields continue to mutually induce each other, producing an electromagnetic wave.


♦ Mean mark 44%.