Answer:
The zoom lens is a bi-convex lens
Step-by-step explanation:
- The convex lens has the property of magnifying the image.
- The bi-convex lens has two concave surfaces.
- This lens has the property that when parallel rays fall on one of the surfaces, it gets converged on the other side.
- So, when an object is placed between the focal length and optic center of the lens, it produces a virtual magnified image of the object.
- The magnification factor is given by the formula

- height of image
- height of the object