Question 167: Magnetism and Matter

Question

A charge Q is moving $$\overrightarrow {dl} $$ distance in the magnetic field $$\overrightarrow {B} $$. Find the value of work done by $$\overrightarrow {B} $$.

Accepted Answer

We know,
$$\overrightarrow F  = q\left( {\overrightarrow v  	imes \overrightarrow B } ight)$$
$$ 	herefore $$ $$\overrightarrow F  \bot \overrightarrow v $$ and $$\overrightarrow F  \bot \overrightarrow B $$
Power (p) $$ = {{dw} \over {dt}}$$
$$ = {{\overrightarrow F .\,\overrightarrow {dl} } \over {dt}}$$
$$ = \overrightarrow F \,.\,{{\overrightarrow {dl} } \over {dt}}$$
$$ = \overrightarrow F \,.\,\overrightarrow v $$
$$ = Fv\cos 	heta $$
$$ = Fv\cos 90^\circ $$
$$ = 0$$
As power supply by the field is zero so, total work done also zero.

Answer

Zero

Answer

$$-$$1

Answer

Infinite

Answer

1

Magnetism and Matter

A charge Q is moving $\overrightarrow {dl} distance in the magnetic field \overrightarrow {B} . Find the value of work done by \overrightarrow {B} $.

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