An AC current is given by I = I₁sinωt + I₂cosωt. A hot wire ammeter will give a reading:

√((I₁² + I₂²)/2)

(I₁ + I₂) / 2√2

(I₁ + I₂) / √2

√((I₁² - I₂²)/2)

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Alternating Current Overview Physics Alternating Current Physics Class 12th

An AC current is given by I = I₁sinωt + I₂cosωt. A hot wire ammeter will give a reading:

Option 1 -

(I₁ + I₂) / 2√2

Option 2 -

√((I₁² + I₂²)/2)

Option 3 -

(I₁ + I₂) / √2

Option 4 -

√((I₁² - I₂²)/2)

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1 Answer

Answered by

Vishal Baghel | Contributor-Level 10

a month ago

Correct Option - 2

Detailed Solution:

I = I? sin (ωt) + I? cos (ωt)

This can be written as I = I? sin (ωt + φ), where I? = √ (I? ² + I? ²)

A hot wire ammeter reads the rms value of the current.

I_rms = I? /√2 = √ (I? ² + I? ²)/√2

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