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3 years ago

7

What is the direction of the magnetic field if an electron moving in the positive x direction experiences a magnetic force in th

e positive z direction

1 answer:

Alex787 [66]3 years ago

7 0

Given :

An electron moving in the positive x direction experiences a magnetic force in the positive z direction.

To Find :

The direction of the magnetic field.

Solution :

We know, force is given by :

$\vec{F}=q(\vec{v}\times \vec{B)}$

Here, q = -e.

$\vec{F}=(-e)(\vec{v}\times \vec{B)}\\\\\hat{k}=(-e)(\hat{i}\times \vec{B})$

Now, for above condition to satisfy :

$\hat{i}\times \vec{B}=-\hat{k}$

So, $\vec{B}=-\hat{j}$

Therefore, direction of magnetic field is negative y direction.

Hence, this is the required solution.

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Answer:

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At what displacement of a sho is the energy half kinetic and half potential? what fraction of the total energy of a sho is kinet

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As we know that KE and PE is same at a given position

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now we will have

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Part b)

KE of SHO at x = A/3

we can use the formula

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The velocity is, by definition: $v=\frac{dx}{dt}$ , so

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