The robot hooru is lost in space, floating around aimlessly, and radiates heat into the depths of the cosmos at the rate of . hooru's surface area is and the emissivity of its surface is . ignore the radiation hooru absorbs from the cold universe. what is hooru's temperature?

150.427 K

Explanation:

The complete question is as follows:

The robot HooRU is lost in space, floating around aimlessly, and radiates heat into the depths of the cosmos at the rate of . HooRU's surface area is and the emissivity of its surface is . Ignore the radiation HooRU absorbs from the cold universe. What is HooRU's temperature?

This problem can be solved by the Stefan-Boltzmann law for real radiator bodies:  

(1)

Where:

is the energy radiated by HooRU

is the Stefan-Boltzmann's constant.  

is the Surface of the robot

is the robot's emissivity

is the effective temperature of the robot (its surface absolute temperature) in Kelvin

So, we have to find from (1):

(2)

Finally:

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.