Physics-
General
Easy
Question
An object is placed 20 cm in front of a plano–convex lens of focal length 15 cm. The plane surface of the lens is silvered. The image will be formed at a distance
- 60 cm to the left of the lens
- 12 cm to the right of the lens
- 60 cm to the right of the lens
- 12 cm to the left of the lens
The correct answer is: 12 cm to the right of the lens
Focal length F of equivalent mirror is given by
or 
cm
The equivalent mirror will concave mirror of focal length 
cm.
Now for a spherical mirror,
Þ 
Þ 
v = –12 cm
Related Questions to study
physics-
A ray of light is incident at the glass-water interface at an angle I, it emerges finally parallel to the surface of water, then the value of mg would be:
A ray of light is incident at the glass-water interface at an angle I, it emerges finally parallel to the surface of water, then the value of mg would be:
physics-General
physics-
A parallel beam of light falls on a convex lens. The path of the rays is shown in the figure. It follows that
A parallel beam of light falls on a convex lens. The path of the rays is shown in the figure. It follows that
physics-General
physics-
Find the size of image formed in the situation shown in figure.
Find the size of image formed in the situation shown in figure.
physics-General
physics-
Locate the image of the point object O in the situation shown in figure. The point C denotes the centre of curvature of the separating surface
Locate the image of the point object O in the situation shown in figure. The point C denotes the centre of curvature of the separating surface
physics-General
physics-
A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is 4/3 and the fish is 12 cm below the surface of water, the radius of the circle in centimeter is
A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is 4/3 and the fish is 12 cm below the surface of water, the radius of the circle in centimeter is
physics-General
physics-
Consider the situation shown in figure. Water (mw = 4/3) is filled in a beaker upto a height of 10 cm. A plane mirror is fixed at a height of 5 cm from the surface of water. Distance of image from the mirror after reflection from the mirror after reflection from it of an object O at the bottom of the beaker is
Consider the situation shown in figure. Water (mw = 4/3) is filled in a beaker upto a height of 10 cm. A plane mirror is fixed at a height of 5 cm from the surface of water. Distance of image from the mirror after reflection from the mirror after reflection from it of an object O at the bottom of the beaker is
physics-General
physics-
One side of a glass slab is silvered as shown in figure. A ray of light is incident on the other side at angle of incidence i = 45º. Refractive index of glass is given as 1.5. The deviation of the ray of light from its initial path when it comes out of the slab is
One side of a glass slab is silvered as shown in figure. A ray of light is incident on the other side at angle of incidence i = 45º. Refractive index of glass is given as 1.5. The deviation of the ray of light from its initial path when it comes out of the slab is
physics-General
physics-
Consider the following diagram The incident ray parallel to the optical axis passing through
Consider the following diagram The incident ray parallel to the optical axis passing through
physics-General
physics-
A layered lens as shown in the figure is made of two materials indicated by different shades. A point object is placed on its axis. The lens will form.
A layered lens as shown in the figure is made of two materials indicated by different shades. A point object is placed on its axis. The lens will form.
physics-General
physics-
A prism of refractive index 
is immersed in water of refractive index 
. For the total internal reflection the correct choice is
A prism of refractive index is immersed in water of refractive index . For the total internal reflection the correct choice is
physics-General
physics-
For a prism PQR the incident and emergent rays are parallel. The minimum value of refractive index of the prism material is
For a prism PQR the incident and emergent rays are parallel. The minimum value of refractive index of the prism material is
physics-General
physics-
When the prism is in the minimum deviation position (Figure). Choose the correct one.
When the prism is in the minimum deviation position (Figure). Choose the correct one.
physics-General
physics-
Figure shows a cross - section of light pipe made of glass fibre of refractive index 1.68. The outer coating of the pipe is made of a material of refractive index 1.44. What is the range of angles of the incident rays with the axis of the pipe for which total internal reflection inside the pipe takes place ?
Figure shows a cross - section of light pipe made of glass fibre of refractive index 1.68. The outer coating of the pipe is made of a material of refractive index 1.44. What is the range of angles of the incident rays with the axis of the pipe for which total internal reflection inside the pipe takes place ?
physics-General
physics-
A vessel contains a slab of glass 8cm thick and of refractive index 1.6 over the slab, the vessel is filled by oil of refractive index m upto height 4.5 cm and also by another liquid i.e., water of refractive index 
and height 6cm as shown in figure. An observer looking down from above, observes that, a mark at the bottom of the glass slab appears to be raised up to position 6cm from the bottom of the slab. The refractive index of the oil is
A vessel contains a slab of glass 8cm thick and of refractive index 1.6 over the slab, the vessel is filled by oil of refractive index m upto height 4.5 cm and also by another liquid i.e., water of refractive index and height 6cm as shown in figure. An observer looking down from above, observes that, a mark at the bottom of the glass slab appears to be raised up to position 6cm from the bottom of the slab. The refractive index of the oil is
physics-General
physics-
In the Figure, AB and BK represent incident and reflected rays. If angle BCF = 35º. Then 
. will be equal to ____ degrees
In the Figure, AB and BK represent incident and reflected rays. If angle BCF = 35º. Then . will be equal to ____ degrees
physics-General
