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2 years ago

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Reflected light from a thin film of oil gives constructive interference for light with a wavelength inside the film of λfilm. By

how much would the film thickness need to be increased to give destructive interference?
A. 2λfilm
B. λfilm
C. λfilm/2
D. λfilm/4

1 answer:

My name is Ann [436]2 years ago

3 0

Answer:D. λfilm/4

Explanation: Destructive interference is a type of wave interference which means the coming together or over-lapping of two opposing waves creating No effect or the Cancellation of the wave impact. An example of destructive wave is when Noise cancel the effect of sound from a head phone.

The film thickness will need to be increased by λfilm/4 for it to be able to give a destructive interference.

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Answer:

1)

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where here:

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The magnetic field produced by a bar magnet has field lines going from the North pole towards the South Pole.

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If we observe the field lines around a magnet, we observe that:

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Therefore, this means that the magnetic field of a magnet is stronger near the North and South Pole.

3)

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It can be applied as follows:

- Direction of index finger = direction of motion of the charge

- Direction of middle finger = direction of magnetic field

- Direction of thumb = direction of the force (for a negative charge, the direction must be reversed)

In this problem:

- Direction of motion = to the right (index finger)

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4)

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5)

The cyclotron frequency of a charged particle in circular motion in a magnetic field is:

$f=\frac{qB}{2\pi m}$

where here:

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6)

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7)

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8)

The flux is calculated as

$\Phi = BA sin \theta$

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Here the loop is rectangular with lenght 15 cm and width 8 cm, so the area is

$A=(0.15 m)(0.08 m)=0.012 m^2$

So the flux is

$\Phi = (5.5)(0.012)(sin 18^{\circ})=0.021 Wb$

See the last 7 answers in the attached document.

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> docx </span>

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> pdf </span>

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2 years ago