Physics-
General
Easy
Question
A point source of light ' S ' at a distance d from the screen A produces light intensity at the centre of the screen. If a completely reflecting mirror M is placed at a distance behind the source as shown in the figure, treating object and its image as inooherent with each other, find the intensity at the centre of the screen.
The correct answer is:
Related Questions to study
physics-
A point object is kept in front of a plane mirror. The plane mirror is doing SHM of amplitude 2 cm. The plane mirror moves along the x-axis and x-axis is normal to the mirror. The amplitude of the mirror is such that the object is always in front of the mirror. The amplitude of SHM of the image is
A point object is kept in front of a plane mirror. The plane mirror is doing SHM of amplitude 2 cm. The plane mirror moves along the x-axis and x-axis is normal to the mirror. The amplitude of the mirror is such that the object is always in front of the mirror. The amplitude of SHM of the image is
physics-General
physics-
A point source of light S is placed in front of two large mirrors as shown. Which of the following observers will see only one image of S?
A point source of light S is placed in front of two large mirrors as shown. Which of the following observers will see only one image of S?
physics-General
physics-
A two eyed man is looking at the junction of two mutually perpendicular mirrors from a far off distance. Assume no reflection to occur from the edge. Then if both the eyes are open
A two eyed man is looking at the junction of two mutually perpendicular mirrors from a far off distance. Assume no reflection to occur from the edge. Then if both the eyes are open
physics-General
physics-
A point source of light ' S ' is placed at a distance 10 cm in front of the center of a mirror of width suspended vertically on a wall. A man walks with a speed 10 cm/s in front of the mirror at a distance of 20 cm from it as shown in figure. Find the maximum time during which he can see the image of the source S in the mirror.
A point source of light ' S ' is placed at a distance 10 cm in front of the center of a mirror of width suspended vertically on a wall. A man walks with a speed 10 cm/s in front of the mirror at a distance of 20 cm from it as shown in figure. Find the maximum time during which he can see the image of the source S in the mirror.
physics-General
physics-
Two plane mirrors are combined to each other as such one is in 
plane and the other is in 
plane. A ray of light travelling along a vector 
is incident on the first mirror. The unit vector in the direction of emergent ray after successive reflections through both the mirrors is
Two plane mirrors are combined to each other as such one is in plane and the other is in plane. A ray of light travelling along a vector is incident on the first mirror. The unit vector in the direction of emergent ray after successive reflections through both the mirrors is
physics-General
physics-
A particle is moving in a circle in front of a plane mirror in the situation as shown in figure. The plane of motion of the particle is perpendicular to the plane of mirror. Then the motion of image of particle with respected to the particle is
A particle is moving in a circle in front of a plane mirror in the situation as shown in figure. The plane of motion of the particle is perpendicular to the plane of mirror. Then the motion of image of particle with respected to the particle is
physics-General
physics-
A plane mirror ' M ' and a concave mirror ' X ' are kept at a separation of 40 cm with their reflecting faces facing each other as shown in figure. An object AB is kept perpendicular to the principal axis in position (1). Considering successive reflections first at mirror ' X' and then at ' M', a real image is formed in front of 'Mat a normal distance 8 cm form it. If the abject is moved to new position (2), the real image is formed at 20 cm from ' M ' with the reflections as described earlier Keeping the object in position (1), if the plane mirror is replaced with a convex mirror ' Y ' of focal length 20 m facing the mirror ' X ' after successive reflections first at ' X ' and then at ' Y ', the final image will be
A plane mirror ' M ' and a concave mirror ' X ' are kept at a separation of 40 cm with their reflecting faces facing each other as shown in figure. An object AB is kept perpendicular to the principal axis in position (1). Considering successive reflections first at mirror ' X' and then at ' M', a real image is formed in front of 'Mat a normal distance 8 cm form it. If the abject is moved to new position (2), the real image is formed at 20 cm from ' M ' with the reflections as described earlier Keeping the object in position (1), if the plane mirror is replaced with a convex mirror ' Y ' of focal length 20 m facing the mirror ' X ' after successive reflections first at ' X ' and then at ' Y ', the final image will be
physics-General
physics-
A thin lens with focal length f to be used as a magnifying glass. Which of the following statements regarding the situation is true?
A thin lens with focal length f to be used as a magnifying glass. Which of the following statements regarding the situation is true?
physics-General
physics-
Which of the following quantities related to a lens depend on the wavelength of the incident light?
Which of the following quantities related to a lens depend on the wavelength of the incident light?
physics-General
physics-
A convex lens forms an image of an object on a screen. The height of the image is 9 cm. The lens is now displaced until an image is again obtained on the screen. The height of this image is 4 cm. The distance between the object and the screen is 90 cm.
A convex lens forms an image of an object on a screen. The height of the image is 9 cm. The lens is now displaced until an image is again obtained on the screen. The height of this image is 4 cm. The distance between the object and the screen is 90 cm.
physics-General
physics-
A curved surface of radius R separates two medium of refractive indices and as shown in figures A and B
Identify the correct statement (s) related to the formation of images of a real object o placed at x from the pole of the concave surface, as shown in figure B
A curved surface of radius R separates two medium of refractive indices and as shown in figures A and B
Identify the correct statement (s) related to the formation of images of a real object o placed at x from the pole of the concave surface, as shown in figure B
physics-General
physics-
The voltage time (V - t) graph for triangular wave having peak value V0 is as shown in figure.
The rms value of V in time interval from 
T is
The voltage time (V - t) graph for triangular wave having peak value V0 is as shown in figure.
The rms value of V in time interval from T is
physics-General
physics-
In a black box of unkown elements (L, C or R or any other combination) an AC voltage 
is applied and current in the circuit was found to be 
Then the unknown elements in the box may be
In a black box of unkown elements (L, C or R or any other combination) an AC voltage is applied and current in the circuit was found to be Then the unknown elements in the box may be
physics-General
physics-
In the circuit shown, a 30V d.c source gives a current 2.0 A as recorded in the ammeter A and 30V a.c source of frequency 100Hz gives a current 1.2A The inductive reactance is
In the circuit shown, a 30V d.c source gives a current 2.0 A as recorded in the ammeter A and 30V a.c source of frequency 100Hz gives a current 1.2A The inductive reactance is
physics-General
physics-
Assertion (A): The average value of 
is zero
Reason (R): The average value of function (t) over a period T is 
Assertion (A): The average value of is zero
Reason (R): The average value of function (t) over a period T is
physics-General
