Electric field intensity at a distance

AI Thread Summary
The discussion centers on calculating electric field intensity based on the power radiated by a bulb. It is noted that the power at a distance r is given by the formula Power radiated/4πr². A participant initially concludes that halving the power results in halving the intensity, leading to the incorrect assumption that E' equals E/2. The correction emphasizes that intensity is proportional to the square of the electric field, indicating that the relationship is not linear. This highlights the importance of understanding the quadratic relationship between intensity and electric field strength.
Jahnavi
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Homework Statement


mcq2.jpg


Homework Equations

The Attempt at a Solution



The radiations from the bulb spread radially outwards such that "Power at a distance r" = Power radiated/4πr2 .

If distance is unchanged and power halved then the intensity should also be halved .

From this I get E' = E/2 .

But this is wrong .
 

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Jahnavi said:

Homework Statement


View attachment 217104

Homework Equations

The Attempt at a Solution



The radiations from the bulb spread radially outwards such that "Power at a distance r" = Power radiated/4πr2 .

If distance is unchanged and power halved then the intensity should also be halved .

From this I get E' = E/2 .

But this is wrong .
Intensity is propotional to square of elecric field
 
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Abhishek kumar said:
Intensity is propotional to square of elecric field

Thanks !
 
Jahnavi said:
Thanks !
Welcome
 

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