Answer:
In my opinion I think that the answer is C sorry If I get this wrong.
If you're using the bulb as a source of light, then it's. 14/60 = 23.3% efficient.
If you're using it to heat a bird nest or a hamster cage, then it's. 46/60 = 76.7% efficient !
It just depends on your point of view, and what you consider 'useful' output.
Answer:
8.4 kW
Explanation:
Using the Stefan-Boltzmann law,
P = εAσT4
Where:
P: Radiation Energy
ε: Emissivity of the Surface. Check emissivity table below of common materials.
A: Surface Area, in m^2.
σ: Stefan-Boltzmann Constant, σ=5.67 × 10-8 W/m2•K4
T: Temperature
Plugging in values,
P = 0.85 x 3.328 x 5.67 x 10^(-8) x 205
P = 8383 W or 8.4 kW
Answer:Aluminium displaces more water
Explanation:
Given
mass of aluminium block=1 kg
mass of lead block= 1 kg
Also we know density of lead
Density of Aluminium
As the density of lead is more than that of Aluminium therefore its volume is lesser than Aluminium for same mass.
Thus aluminium displaces more amount of water as compared to lead.
