Problem in electrostatics: E-field near 2 point charges

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The discussion revolves around a problem involving the electric field and potential energy near two point charges of unequal magnitudes. The user calculates the electric field at a large distance, concluding that options c and d are correct, while option a is incorrect. There is confusion regarding the calculation of angle beta, but it is noted that this angle is not necessary to disqualify option b. The problem originates from the 2016 NEST exam in India. The conversation highlights the complexities of electrostatics in relation to point charges.
ubergewehr273
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Homework Statement


Refer the image.

Homework Equations


kq1q2/r^2 = F
Potential energy = kq1q1/r

The Attempt at a Solution


Obviously since both charges are unequal in magnitude option a is incorrect.
Calculating field at large distance r,
E = kq1/r^2 - kq2/r^2
= kq2/r^2
Also potential energy at q1 is lesser than near q2 for negative charge.
So options c,d are correct. However I don't understand how the angle beta can be calculated from the given information.
 

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ubergewehr273 said:
However I don't understand how the angle beta can be calculated from the given information.
No need to calculate the angle to disqualify answer b.
 
Doc Al said:
No need to calculate the angle to disqualify answer b.
I'm sorry but I don't quite understand. The answers given are b,c,d.
 
Hmm. What book is this from?
 
Doc Al said:
Hmm. What book is this from?
It's from an exam paper called NEST (National Entrance Screening Test) conducted in India. Its for the year 2016.
 

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