Two point charges a and b , whose magnitudes are same are positioned at a certain distanc

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1. Electric Charges and Fields

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Two point charges $a$ and $b$, whose magnitudes are same are positioned at a certain distance from each other with a at origin. Graph is drawn between electric field strength at points between $a$ and $b$ and distance $x$ from a $E$ is taken positive if it is along the line joining from to be. From the graph, it can be decided that

A

$a$ is positive, $b$ is negative

B

$a$ and $b$ both are positive

C

$a$ and $b$ both are negative

D

$a$ is negative, $b$ is positive

Solution

From graph it can be observed that field is always in the $+ve$ direction. This means a must $be +ve$ and $b$ must be $-ve.$

If both are positive, then field must become zero and change it's direction afterward.

If both are negative, then field must be in$-ve$ direction when it is close to $a.$

$a-ve$ and $b +ve$ means field must always $be-ve.$

Standard 12

Physics

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