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3 years ago

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Photoelectrons with a maximum speed of 7.00 · 105 m/s are ejected from a surface in the presence of light with a frequency of 8.

00 · 1014Hz. If the mass of an electron is 9.1 · 10-31 kg, calculate the maximum kinetic energy of a single electron, in joules.
_____ J

6.3 x 10-25
4.4 x 10-19
3.2 x 10-25
2.2 x 10-19

1 answer:

lord [1]3 years ago

4 0

This is just testing your ability to recall that kinetic energy is given by:

<span>k.e. = ½mv² </span>

<span>where m is the mass and v is the velocity of the particle. </span>

<span>The frequency of the light is redundant information. </span>

<span>Here, you are given m = 9.1 * 10^-31 kg and v = 7.00 * 10^5 m/s. </span>
<span>Just plug in the values: </span>

<span>k.e. = ½ * 9.1 * 10^-31 * (7.00 * 10^5)² </span>
<span>k.e. = 2.23 * 10^-19 J
so it will be d:2.2*10^-19 J</span>

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Answer:

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$F=qvB sin \theta$

where here:

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The density of the field lines at any point tells how strong is the magnetic field at that point.

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

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3)

The right hand rule gives the direction of the force experienced by a charged particle moving in a magnetic field.

It can be applied as follows:

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

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Substituting, we find:

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8)

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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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