Two Large Closely Spaced Concentric Spheres (Both of Which Are

question 31

Multiple Choice

Two large closely spaced concentric spheres (both of which are perfect black body radiators) are maintained at temperatures of 127°C and ² 7°C respectively. The space in between the two spheres is evacuated. Taking Stefan Boltzmann constant as 5.67 x 10⁸ watt m²K the rate of radiation in watts per sq. m between the two spheres is approximately

• A)992
• B)762
• C)37,500 kg
• D)852
• E)666

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Definitions:

Myelin Sheath

A fatty layer that surrounds nerve fibers, providing insulation and enhancing electrical transmission along the neuron.

Nerve Impulse Conduction

The process by which electrical signals are transmitted along a nerve fiber, facilitating communication between the brain and different parts of the body.

Electric Insulator

A material whose internal electric charges do not flow freely, making it capable of preventing the passage of electric current.

Ependymal Cells

Glial cells that line the ventricles in the brain and the central canal of the spinal cord, involved in the production and circulation of cerebrospinal fluid.