Physics-
General
Easy

Question

If the surface temperature of the sun and its mass were to remain constant and its radius were to increase by a factor of 2, the equilibrium temperature of a planet (Tp) would

  1. decreases by a factor of 2    
  2. increases by a factor of square root of 2    
  3. increase by a factor of 23/2    
  4. increase by a factor of 4    

The correct answer is: increase by a factor of 4

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