The distance between the eyepiece and the objective lens in a certain compound microscope is 23.0 cm. The focal length of the eyepiece is 2.50 cm and that of the objective is 0.400 cm. What is the overall magnification of the microscope?

The distance between the objective and eyepiece lenses in a microscope is 21 cm . The objective lens has a focal length of 5.0 mm .   What eyepiece focal length will give the microscope an overall angular magnification of 350?

A camera lens used for taking close-up photographs has a focal length of 25.0 mm. The farthest it can be placed from the film is 30.0 mm. (a) What is the closest object (in mm) that can be photographed? ANS: ___ mm   What is the magnification of this closest object? ANS: _____ X

A microscope has an objective lens with a focal length of 16.22 mm and an eyepiece with a focal length of 9.06 mm. With the length of the barrel set at 33.0 cm, the diameter of a red blood cell's image subtends an angle of 1.43 mrad with the eye. If the final image distance is 33.0 cm from the eyepiece, what is the actual diameter of the red blood cell? Hint: To solve this equation, go back to basics and use the thin-lens equation. ?m

A glass lens (?=1.60) has a focal length of ?=−32.7 cm and a plano‑concave shape. Calculate the magnitude R of the radius of curvature of the concave surface. R = ?cm If a lens is constructed from the same glass to form a plano‑convex shape with the same radius of curvature magnitude, what will the focal length f' be? f' = ? cm

The objective lens of a microscope is a planoconvex (flat on one side) lens that has a short focal length of 7.6 mm. The focusing knob on the microscope moves the object toward or away from the objective lens. The microscope is designed so that the object will be seen in focus through the eyepiece when the objective lens forms a real image of the object 160 mm behind the objective lens. (a) At what object distance in mm is the microscope focused? (b) What is the lateral magnification of the objective lens?(c) Account for the resulting image shown in the figure, i.e. using your calculations, justify that indeed the image is real, magnified, and inverted.

A camera is equipped with a lens with a focal length of 25 cm. When an object 1.3 m (130 cm) away is being photographed, how far from the film should the lens be placed? cm

An object is placed at a distance of 10.0 cm from a convex lens with a focal length of 15.0 cm, and a virtual image is formed .  Calculate the magnification factor for the image.

A concave spherical mirror has a radius of curvature, R = 18.2 cm. If an object is placed 53.4 cm in front of the lens, what is the magnification of the image produced?

The distance between the eyepiece and the objective lens in a certain compound microscope is 10.4 cm. The focal length of the objective is 0.430 cm, and that of the eyepiece is 1.40 cm. Find the overall magnification of the microscope. (The near point of the eye is 25 cm. Assume that the object is placed at the focal point of the objective lens, and one places the eyepiece at the near point of the eye.)