Concave Mirror Functionality
Concave mirrors are used in torches and car headlights because they possess a unique property related to light reflection.
Parallel Beam Production
The primary reason for using a concave mirror in these applications is its ability to produce a parallel beam of light.
- When a light source (like a bulb) is placed at the focal point (F) of the concave mirror, the light rays emanating from it strike the mirror's surface.
- According to the laws of reflection, these rays are reflected outwards in a highly parallel beam.
- This focused, parallel beam travels a significant distance without spreading out rapidly, which is essential for effective illumination in torches and for the headlights of vehicles to light up the road ahead clearly.
Incorrect Option Explanations
- Option 1 is incorrect because concave mirrors can form both real and virtual images depending on the object's position relative to the focal point and center of curvature.
- Option 2 is incorrect; concave mirrors converge light, which typically increases the intensity or brightness in the direction of the beam, rather than reducing it.
- Option 4 is incorrect as concave mirrors are designed to focus or collimate light into a beam, not scatter it in all directions. Scattering is typical of diffuse surfaces.
Therefore, the capability to generate a parallel beam of light makes concave mirrors ideal for torches and headlights.
Similar Questions
An object is placed at a distance of 20 cm from a convex lens of focal length 10 cm. The image is formed at a distance of:
When white light is dispersed by a glass prism into seven colours, out of the following colours which colour will be deviated the least?
When a ray of light travels from a denser medium to a rarer medium, it bends ________.
- If the angle of incidence formed on a concave mirror at a point is 30 ° then the angle of reflection will be:
- The line joining the centre of curvature and the pole of a given spherical mirror is called __________.
- When white light passes through a prism, different colours of light bend through different angles. Which colour bends the least and which bends the most?
- A symmetrical biconvex lens of focal length '\(f\)' is cut into four identical pieces along and perpendicular to its principal axis The focal length of each of four pieces is
- Complete the statement with correct option.
In dispersion without deviation,_________________ - A thin prism $P_1$ of angle $4^\circ$ and refractive index 1.54 is combined with another thin prism $P_2$ of refractive index 1.72 to produce dispersion without deviation. The angle of $P_2$ is
Which of the following is NOT the use of a concave mirror?
Important Questions from Optics
Who was the first one to use a glass prism to obtain the spectrum of sunlight?
Twinkling of stars is due to:
In which a convex mirror is used?
A. Rear View mirrors in vehicles
B. Glass windows
C. Makeup Mirror
D. Kaleidoscope
An object is placed 10 cm in front of a lens. The image formed is real, inverted and of same size as the object. What is the focal length and nature of the lens?
The power of a lens is -2.5 D. The type of lens and its focal length are respectively:
