A lens is cut into two equal halves: Along the principal axis.
What will be the focallength of each half?
Download our app for free and get started
If the lens can be cut on the principal axis and then there is no change in length of the focus of lens because the radius of curvature will remain the same, hence the focal length will remain unchanged.
Download our app
and get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
A ray of light is incident on a convex mirror as shown. Redraw the diagram and complete the path of this ray after reflection from the mirror. Mark angle of incidence and angle of reflection on it.
Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is $3 \times 10^8 m s ^{-1}$.
Light travels through air at 300 million $ms ^{-1}$. On entering water it slows down to 225 million $ms ^{-1}$. Calculate the refractive index of water.
To find-the image-distance for varying object-distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that he gradually moves the object towards the lens and each time focuses its image of the screen.
In which direction - towards or away from the lens, does he move the screen to focus the object?
What happens to the size of the image - does it increase or decrease?
What happen when he moves the object very close to the lens?