Two otherwise identical objects have temperatures of 1000 K and 1200 K, respectively. The object at 1200 K emits roughly twice as much radiation as the object at 1000 K. (T/F)

Respuesta :

Answer:

True

The object with the temperature at 1200K emits twice as much radiation as the object at 1000K.

Explanation:

The Stefan-Boltzmann law establishes how much an object radiates as a consequence of its temperature.

[tex]R_{p} = \sigma \cdot T^{4}[/tex]   (1)

Where [tex]R_{p}[/tex] is the radiant power, [tex]\sigma[/tex] is the Stefan-Boltzmann constant and T the temperature.

Case for the object with [tex]T = 1000K[/tex]:

[tex]R_{p} = (5.67x10^{-8} W/m^{2} K^{4})(1000K)^{4}[/tex]

[tex]R_{p} = 56700 W/m^{2}[/tex]

Case for the object with [tex]T = 1200K[/tex]:

[tex]R_{p} = (5.67x10^{-8} W/m^{2} K^{4})(1200K)^{4}[/tex]

[tex]R_{p} = 117573 W/m^{2}[/tex]

[tex]R_{p}diff = \frac{117573 W/m^{2}}{56700 W/m^{2}}[/tex]

[tex]R_{p}diff = 2.07[/tex]

Hence, the object with the temperature at 1200K emits twice as much radiation as the object at 1000K.

Answer:

True

P2/P1 ~= 2

Therefore, The object at 1200 K emits roughly twice as much radiation as the object at 1000 K

Explanation:

According to Stefan-Boltzmann law, which states that the amount of thermal energy radiated by an object per unit area per second is directly proportional to the fourth power of its absolute temperature. It can be stated mathematically as;

P/A = c.T^4 .......1

Where;

P = radiated power

A = surface area

c = stefan's constant

T = absolute temperature.

From 1;

P = cAT^4

For the two cases

P1 at T1 = 1000K

P2 at T2 = 1200K

Since the object is identical

A1 = A2 = A

P2/P1 = cA(T2)^4 ÷ cA(T1)^4

P2/P1 = (T2)^4/(T1)^4

P2/P1 = (1200)^4/(1000)^4

P2/P1 = 2.073

P2/P1 ~= 2

Therefore, The object at 1200 K emits roughly twice as much radiation as the object at 1000 K