Problem 61.
What is the focal length of a convex mirror whose radius of curvature is 30 cm?
Solution
Problem 62.
A candle 8 cm high is 40 cm in front of a mirror whose focal length is 70 cm. What is the height of the image?
Solution
Problem 63.
An object 6 cm long is placed 30 cm in front of a mirror with focal length of 50 cm. What are the position and the height of the image?
Solution
Problem 64.
Find the index of refraction of the glass used in a planoconcave lens of focal length 10 cm whose concave surface has a radius of 5 cm?
Solution
Problem 65.
A doubleconvex lens has surfaces whose radii are both 40 cm. The index of refraction of the glass of the lens is 1.6. What is the focal length of the lens?
Solution
Problem 66.
The distance between the object and the virtual image formed by a lens is 10 cm.The size of the image is 3 times the size of the object. Find the focal length of the lens and the distance between the object and the lens.
Solution
Problem 67.
The distance between the object and the virtual image formed by a lens is 20 cm. The size of the image is half the size of the object. Find the focal length of the lens and the distance between the object and the lens.
Solution
Problem 68.
The images formed by a lens is observed on a screen. The distance between the object and the image is 20 cm. The size of the image is twice the size of the object. What is the focal length of the lens? What is the distance between the object and the lens?
Solution
Problem 69.
The image formed by a lens is inverted and its size is two times the size of the object. Find the focal length of the lens and the distance between the object and the lens if the distance between the image and the object is 20 cm.
Solution
Problem 70.
The image formed by a lens is upright and two times the size of the object. The distance between the image and the object is 10 cm. Find the focal length of the lens and the distance between the object and the lens.
Solution
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