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 .
The North Pole would be your answer
The bimetallic strip in a fire alarm is made of two metals with different expansion rates bonded together to form one piece of metal. Typically, the low-expansion side is made of a nickel-iron alloy called Invar, while the high-expansion side is an alloy of copper or nickel. The strip is electrically energized with a low-voltage current. When the strip is heated by fire, the high-expansion side bends the strip toward an electrical contact. When the strip touches that contact, it completes a circuit that triggers the alarm to sound. The width of the gap between the contacts determines the temperature that will set off the alarm.
Answer:
Here the circuit in which a 4Ω resistor resistor is connected in series and two 8Ω resistor resistors are connected in parallel. Also, ammeter and voltmeter connected in series and parallel circuit respectively.
Now,
The maximum power of each resistance is 16 W
The 4Ω resistor is linked in series with the circuit.
so, P o w e r = I
two
R, here i is the current through the resistor resistor R
1 6 = I
two
∗ 4 Ω
i = 2A
Now 2A passes through parallel resistors of 8Ω resistance.
we know that, in parallel, the potential difference must be constant,
the current is divided into two parts, because the same resistance current in each resistance will be half. then the current through each resistor in parallel is
2 A
two
.
= 1 A
So finally the current through the 4Ω resistor = 2 A
current through each 8Ω resistor = 1 A
Explanation:
I hope this answer has helped you
