Suppose that the lower half of the concave mirror’s reflecting surface in the given figure is covered with an opaque (non-reflective) material. What effect will this have on the image of an object placed in front of the mirror?
1. | the image will show only half of the object |
2. | the image will show the whole of the object |
3. | the intensity of the image will be low |
4. | both (2) and (3) |
A mobile phone lies along the principal axis of a concave mirror, as shown in the figure. Then,
1. | the magnification is not uniform due to the length of the object along the principal axis. |
2. | the distortion of the image depends on the location of the phone with respect to the mirror. |
3. | both (1) and (2) |
4. | none of these |
An object is placed at \(10\) cm in front of a concave mirror with a radius of curvature of \(15\) cm. The magnification of the image is:
1. \(-3\)
2. \(3\)
3. \(1\)
4. \(-1\)
An object is placed at \(5\) cm in front of a concave mirror with a radius of curvature of \(15\) cm. The nature of the image is:
1. magnified, real, and inverted
2. magnified, virtual, and erect
3. magnified, real, and erect
4. none of these
Suppose while sitting in a parked car, you notice a jogger approaching towards you in the side view mirror of R = 2 m. If the jogger is running at a speed of , how fast does the image of the jogger appear to move when the jogger is 39 m away?
The earth takes 24 h to rotate once about its axis. How much time does the sun take to shift by 1° when viewed from the earth?
1. 3 minutes
2. 2 minutes
3. 1 minutes
4. 4 minutes
Light from a point source in the air falls on a convex spherical glass surface (n = 1.5 and radius of curvature = 20 cm) of a glass medium which extends till infinity on other side . The distance of the light source from the glass surface is 100 cm. At what position the image is formed?
1. | at a distance of 200 cm from the glass surface, in the direction of incident light. |
2. | at a distance of 100 cm from the glass surface, in the direction of incident light. |
3. | at a distance of 200 cm from the glass surface, in the opposite direction of incident light. |
4. | at a distance of 100 cm from the glass surface, in the opposite direction of incident light. |
A magician during a show makes a glass lens with n = 1.47 disappear in a trough of liquid. What is the refractive index of the liquid?
1. 1.47
2. 1.33
3. 0.66
4. 1.5
If \(f=0.5\) m for a glass lens, what is the power of the lens?
1. \(+0.4\) D
2. \(+4.0\) D
3. \(+0.2\) D
4. \(+2.0\) D
The radii of curvature of the faces of a double convex lens are \(10\) cm and \(15\) cm. Its focal length is \(12\) cm. What is the refractive index of glass?
1. \(1.3\)
2. \(1.2\)
3. \(1.5\)
4. \(1.4\)