List of top Physics Questions on spherical lenses

An object of height \( 4 \, \text{cm} \) is placed \( 15 \, \text{cm} \) in front of a convex lens of focal length \( 10 \, \text{cm} \). The height of the image formed is:

When an object is placed at a distance of 40 cm from a convex lens, a real image is formed at a distance V from the lens. If the convex lens is replaced with a concave lens of same focal length, then the change in the position of the image is

A plano-convex lens fits exactly into a plano-concave lens. Their plane surfaces are parallel to each other. If lenses are made of different materials of refractive indices \( \mu_1 \) and \( \mu_2 \) and \( R \) is the radius of curvature of the curved surface of the lenses, then the focal length of the combination is

Every lens has _____ focal points.

Which of the following indicates lens formula?

Any light ray passing through the principal axis of lens is \dots

If a convex lens has to form the image of an object at infinity, where should the object be placed?

If a thin lens of focal length 20 cm is in contact with another lens of power 4 D, then the effective power of the combination is

A convex lens of focal length 20 cm is placed in contact with a concave lens of focal length 40 cm. The power of the combination is

An object is placed at a distance of 30 cm from a convex lens of focal length 100 cm when it moves 5 cm towards the lens how much is the image being shifted?

An effective power of a combination of 5 identical convex lens having focal length f= 20 cm is

A circular loop is made from a wire of length 6m. If 2A current passes through the circular loop, what is the magnetic moment of the loop?

A spherical interface lens of radius $R$ separates two media of refractive indices $1$ and $1.4$ respectively as shown in the figure below. A point source is placed at a distance of $4R$ in front of spherical interface. The magnitude of the magnification of point source image is ————.

What is the focal length of a lens if its power is +2 D?

A convex lens of focal length $\frac{1}{3} \text{ m}$ forms a real, inverted image twice the size of the object. The distance of the object from the lens is

Two thin lenses having $\text{R}_1, \text{R}_2$ as the radii of curved surfaces are kept coaxially together. Their power is proportional to}

A convex lens of focal length $\frac{1}{3} \text{ m}$ forms a real, inverted image twice the size of the object. The distance of the object from the lens is

A convex lens has a focal length of 10 cm. What is the magnification produced when the object is placed 30 cm from the lens?