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Lenses/Radius of Curvature

Hi. Can someone please show me how to do the following problem? Thank you. "When a patient is being fitted with contact lenses, the curvature of the patient's cornea is measured with an instrument known as a keratometer. A lighted object is held near the eye, and the keratometer measures the magnification of the image formed

Cosine and Sine Fourier Transforms

Problem 1: Consider a function f(t) that is zero for t<0 and equals e^-t/2r for t>=0. Find its Cosine and Sine Fourier Transforms A(w) and B(w). Make a nice plot of A(w) and B (w). Find a convenient value of tau. Problem 2: Find the Cosine and Sine Fourier Transforms A(w) and B(w) for the sinusoidal pulse f(t) given by f(t

Mirrors And Lens: Find Position and Magnification

An object is placed 18 cm to the left of a converging lens of focal length 27 cm. A diverging lens of focal length 10 cm is 25 cm to the right of the converging lens. Find the position and magnification of the final image?

Mirrors And Lens

The nickel's image has four times the diameter of the nickel when the lens is 2.70 cm from the nickel. Determine the focal length of the lens?

Angular spread of laser

Calculate the angular spread of a laser beam due to diffraction if the beam emerges through a 2.90mm diameter mirror. Assume that lambda = 686nm.

Calculating angle of incidence

A person stands 3.4m in front of a wall that is covered floor-to-ceiling with a plane mirror. His eyes are 2.0m above the floor. He holds a flashlight between his feet and manages to point it at the mirror. At what angle of incidence must the light strike the mirror so the light will reach his eyes?

Starting a fire with a mirror and sunlight.

Which kind of spherical mirror, concave or convex, can be used to start a fire with sunlight? For the best results, how far from the mirror should the paper to be ignited be placed?

Image formed by a concave mirror

For an image formed by a concave mirror to be a point, the object must be: A) between the principle focus and the mirror B) at the center of curvature C) at an infinite distance D) at the principle focus