A typical nuclear reactor generates 1000MW (1000MJ/s of electrical energy. In doing so, it produces 2000MW of waste heat that must be removed from the reactor to keep it from melting down. Many reactors are sited next to large bodies of water so that they can use the water for cooling. Consider a reactor where the intake water is at 18C. State regulations limit the temperature of the output water to 30C so as not to harm aquatic organisms. How many liters of cooling water have to be pumped through the reactor each minute?

2391200 L/min

Explanation:

Let water capacity = 4182 Jkg/C and water density ρ be 1 kg/L

For each second we need to dissipate of heat on 18C water to 30C water. We can use the following heat exchange equation to find out the mass rate

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.