Electric field intensity at a distance

[Jahnavi]

Homework Statement

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 .

 

[Abhishek kumar]

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

 

[Jahnavi]

Intensity is propotional to square of elecric field

Thanks !

 

[Abhishek kumar]

Thanks !

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