You Dip a Wire Loop into Soapy Water (N =

question 88

Multiple Choice

You dip a wire loop into soapy water (n = 1.33) and hold it up vertically to look at the soap film in white light.The soap film looks dark at the top because it has sagged,and its thickness there is nearly zero,causing the reflected wavelengths to interfere destructively.Part way down the loop you see the first red band of the reflected white light.What is the thickness of the soap film there? (Take the wavelength of red light to be 680 nm.)

• A)130 nm
• B)170 nm
• C)220 nm
• D)250 nm
• E)340 nm

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Definitions:

Ventricular Hydrocephalus

Ventricular hydrocephalus is a condition characterized by excessive accumulation of cerebrospinal fluid in the ventricles of the brain, leading to increased pressure and potential damage to brain tissues.

Blockage of CSF

An obstruction in the flow of cerebrospinal fluid (CSF), which can lead to conditions like hydrocephalus, influencing brain pressure.

Thalamus

A brain structure that acts as a relay center, processing and transmitting sensory and motor signals to the cerebral cortex.

Third Ventricle

A median cleft between the two halves of the brain that is filled with cerebrospinal fluid.