Test: Light - Class 7 MCQ

Rectilinear propagation of light refers to the fact that light travels in a straight line. This means that when light passes through a transparent medium, such as air, it will continue to travel in a straight line until it encounters an obstacle or another medium.

Shadows are formed due to the rectilinear propagation of light. When an object blocks the path of light, the light cannot pass through that object and a shadow is formed on the opposite side of the object.

Reflection can occur on any surface, although the quality of the reflection may vary depending on the smoothness of the surface. When light strikes a surface, it may reflect off that surface at the same angle at which it struck the surface.

Convex mirrors are commonly used in rearview mirrors because they provide a wider field of view than concave mirrors. This is because convex mirrors diverge light, which means that they spread light out and make objects appear smaller.

Plane mirrors always produce virtual images, which are images that cannot be projected onto a screen. Virtual images are formed by the apparent intersection of reflected rays of light.

Concave mirrors can produce both real and virtual images, depending on the location of the object relative to the mirror. Real images are formed when the object is located beyond the focal point of the mirror, while virtual images are formed when the object is located between the mirror and the focal point.

Convex mirrors always produce virtual images, regardless of the location of the object relative to the mirror. This is because convex mirrors diverge light, which means that they spread light out and make objects appear smaller.

Concave lenses always produce virtual images, regardless of the location of the object relative to the lens. This is because concave lenses diverge light, which means that they spread light out and make objects appear smaller.

A reflecting surface is a surface that reflects light, such as a polished metal plate. When light strikes a reflecting surface, it is reflected back in a specific direction.

Spherical mirrors can be either concave or convex, depending on the curvature of the mirror. The shape of a spherical mirror affects how light is reflected off of it.

Concave mirrors can be used to create a magnified image when the object is located beyond the focal point of the mirror. This is because concave mirrors converge light, which means that they bring light rays together to form an image.

When light passes through a convex lens, it is refracted inwards. This means that the light rays are bent towards the center of the lens, which can cause the image to appear larger or closer.

Colors are a property of light, which is made up of different wavelengths of electromagnetic radiation. Different colors have different wavelengths and frequencies.

Blue light has the shortest wavelength of the colors listed. This means that it has a higher frequency than the other colors and carries more energy.

Newton's disc is a device that produces a spectrum of colors when it is rotated. This is because the different colors of light have different wavelengths and are refracted by the disc at different angles.

Shadows can be larger or smaller than the object casting them, depending on the position of the light source and the distance between the object and the surface on which the shadow is being cast.

A plane mirror is a mirror with a flat surface. When light strikes a plane mirror, it is reflected back in a specific direction, creating a virtual image.

The focal point of a concave mirror is located behind the mirror. This is where light rays that are parallel to the mirror's axis converge after being reflected off the mirror.

Convex lenses are used in many optical devices, including magnifying glasses, camera lenses, and telescope lenses. They are thicker in the middle than at the edges and converge light.

Concave lenses always produce virtual images, regardless of the location of the object relative to the lens. This is because concave lenses diverge light, which means that they spread light out and make objects appear smaller.