Find the minimum thickness (in nm) of a soap bubble that appears red when illuminated by white light perpendicular to its surface. Take the wavelength to be 680 nm, and assume the same index of refraction as water.

The thickness of the soap bubble is 170 nm.

Explanation:

Given that,

Wavelength of light,

We need to find the minimum thickness of a soap bubble that appears red when illuminated by white light perpendicular to its surface. Let t is the minimum thickness of the film. When reflection is taking place at an interface, then the condition for constructive interference is given by :

So, the thickness of the soap bubble is 170 nm.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

at right angles to each other