Answer:
Explanation:
Intensity of light is inversely proportional to distance from source
I ∝ 1 /r² where I is intensity and r is distance from source . If I₁ and I₂ be intensity at distance r₁ and r₂ .
I₁ /I₂ = r₂² /r₁²
If r₂ = 4r₁ ( given )
I₁ / I₂ = (4r₁ )² / r₁²
= 16 r₁² / r₁²
I₁ / I₂ = 16
I₂ = I₁ / 16
So intensity will become 16 times less bright .
"16 times " is the answer .
Answer:

Explanation:
Given data

To find
Mutual inductance of the two-coil system
Solution
The mutual inductance given as:
M= (-VΔt)/ΔI
Substitute the given values
So

Answer:
c. testing student opinions
Explanation:
opinions aren't factual and they would not aide an experiment if it wasn't for a social experiment.
Answer:
a. 165.5 V
b. 7.78 A
Explanation:
Here is the complete question
The RMS potential difference of an AC household outlet is 117 V. a) What is the maximum potential difference across a lamp connected to the outlet? b) If the RMS current through the lamp is 5.5 A, what is the maximun current through the lamp.
Solution
a. The maximum potential difference across the lamp V₀ = √2V₁ where V₁ = rms value of potential difference = 117 V
V₀ = √2V₁ = √2 × 117 V = 165.5 V
b. The maximum current through the lamp I₀ = √2I₁ where I₁ = rms value of current = 5.5 A
V₀ = √2V₁ = √2 × 5.5 A = 7.78 A