A particle moves towards a concave mirror of focal length 30 cm along its axis and with a constant speed of 4 cm/ sec. What is the speed of its image when the particle is at 90 cm from the mirror?
We know that if
⇒ v = – 45 cm
Substitute the values
The size of the face of a dancer is 24 cm ×16 cm. The minimum size of a plane mirror required to see the face of dancer completely by
(i) one eyed dancer. (ii) two eyed dancer
(Distance between the eyes is 4 cm)
A ray of light falls on a plane mirror. When the mirror is turned, about an axis at right angle to the plane of the mirror through 20o, the angle between the incident ray and new reflected ray is 45o. The angle between the incident ray and original reflected ray is
A fluorescent lamp of length 1 m is placed horizontal at a depth of 1.2 m below a ceiling. A plane mirror of length 0.6 m is placed below the lamp parallel to and symmetric to the lamp at a distance 2.4 m from it. The length of the reflected patch of light on the ceiling is
Two plane mirrors are placed parallel to each other. A point object is placed between them. The distance of image formed in one of the mirror is in
Two plane mirrors are parallel to each other and spaced 20 cm apart. A luminous point object is placed between them and 5 cm from one mirror. What are the distances from each mirror of the three nearest images in each?
If two adjacent walls and the ceiling of a rectangular room are mirror surfaced, then how many images of himself, a man can see?
Two bodies A and B are moving towards a plane with speeds VA and VB respectively as shown in figure. The speed of image of A with respect to the body B is
A beam of convergent light converges to a point 0.5 in front of the mirror after reflection at a convex mirror but in the absence of the mirror the beam converges to a point 0.2 behind the mirror. The radius of curvature of the mirrors is
A particle executes SHM in front of a concave mirror of radius 1 m, about the centre of curvature, with very small amplitude a. The amplitude of oscillation of the image is
A thin flat glass plate is placed in front of a convex mirror. At what distance b from the plate should a point source of light S be placed so that its image produced by the rays reflected from the front surface of the plate coincides with the image formed by the rays reflected from the mirror? The focal length of the mirror is f = 20 cm and the distance from the plate to the mirror a = 5 cm. How can the coincidence of the images be established by direct observation