An object at 30.0°C has its temperature increased to 41.0°C.The power then radiated by this object increases by how many percent?
A)10.0
B)15.3
C)3.63
D)36.7
E)96.5

Question

Quizplus · Accepted Answer

The power radiated by an object is given by the Stefan-Boltzmann law: 
P = εσAT⁴
where P is power, ε is the emissivity (assumed to be 1 for simplicity), σ is the Stefan-Boltzmann constant, A is the surface area, and T is the temperature in Kelvin. 
The ratio of the powers (P2/P1) can be written as: 
P2/P1 = (T2/T1)⁴
where T1 and T2 are the initial and final temperatures in Kelvin. 
Using this formula, we can find the ratio of the powers for the given temperatures: 
P2/P1 = (314/303)⁴ = 1.153 
This means that the power is increased by 15.3% (100% x 0.153) when the temperature is increased from 30°C to 41°C. Therefore, the answer is (B).

An Object at 30