Image Formation in Concave Mirror

Q.

Arrange the following steps of an experiment to determine the focal length of a concave mirror in proper order.
(A) Focus the mirror to a distant object.
(B) Place the concave mirror on a V shaped stand.
(C) Measure the distance between the screen and the mirror.
(D) Adjust the position of the screen, such that a clear image is formed on it.

1. BCAD

2. CDBA

3. BADC

4. BDAC

Q. A concave mirror is used to focus the image of a flower on a nearby well 120cm from the flower. If a lateral magnification of 16 is desired, the distance of the flower from the mirror should be

1. 8 cm
2. 12 cm
3. 80 cm
4. 120 cm

Q. The figure shows a spherical concave mirror of radius of curvature $R=10\text{cm}$, with its pole at $(0,0)$ and principal axis along $x-$axis. There is a point object $O$ at $(-40\text{cm},1\text{cm})$. The position of the image is :

1. $(\frac{-40}{7}\text{cm},\frac{-1}{7}\text{cm})$
2. $(\frac{+40}{7}\text{cm},\frac{+1}{7}\text{cm})$
3. $(\frac{-20}{7}\text{cm},\frac{-1}{7}\text{cm})$
4. $(\frac{+20}{7}\text{cm},\frac{+1}{7}\text{cm})$

Q. An object placed in front of a concave mirror of focal length $0.15\text{m}$ produces a virtual image which is twice the size of the object. The position of the object from the mirror as per sign convention is

1. $-6.5\text{cm}$
2. $+6.5\text{cm}$
3. $-7.5\text{cm}$
4. $+7.5\text{cm}$

Q.

An object 5cm tall is placed 1m from a concave spherical mirror which has a radius of curvature of 20cm The size of the image is

1. 0.11cm
2. 0.50cm

3. 0.55cm

4. 0.60cm

Q. A point object is placed at a distance of 10cm and its real image is formed at a distance of 20cm from a concave mirror. If the object is moved by 0.1cm towards the mirror, the image will shift by about

1. 0.4cm away from the mirror
2. 0.4cm towards the mirror
3. 0.8cm away from the mirror
4. 0.8cm towards the mirror

Q. An object is placed between the centre and focus of a concave mirror. The image formed is .

1. virtual
2. No image
3. real

Q.

A concave mirror is placed at the bottom of an empty tank with face upwards

and axis vertical. When sunlight falls normally on the mirror, it is

focussed at distance of 32 cm from the mirror. If the tank filled with water

upto a height of 20 cm, then the sunlight will now get focussed at

[UPSEAT 2002]

1. 16 cm above water level

2. 9 cm above water level

3. 24 cm below water level

4. 9 cm below water level

Q. An object 2.5 cm high is placed at a distance of 10 cm from a concave mirror of radius of curvature 30 cm The size of the image is

1. 9.2 cm
2. 10.5 cm
3. 5.6 cm
4. 7.5 cm

Q.

In which of the following cases, the rays after reflection from a concave mirror diverge:

1. When the object is place at infinity

2. When the object is placed between center of curvature and the focus

3. When the object is placed between focus and the pole

4. Never. Concave mirror is a converging mirror.

Q. Which of the following is a correct graph between object distance$\left(u\right)$ and image distance $\left(v\right)$ for a concave mirror as per the sign convention?

1. 
2. 
3. 
4. 

Q. The figure shows a spherical concave mirror of radius of curvature $R=10\text{cm}$, with its pole at $(0,0)$ and principal axis along $x-$axis. There is a point object $O$ at $(-40\text{cm},1\text{cm})$. The position of the image is :

1. $(\frac{-40}{7}\text{cm},\frac{-1}{7}\text{cm})$
2. $(\frac{+40}{7}\text{cm},\frac{+1}{7}\text{cm})$
3. $(\frac{-20}{7}\text{cm},\frac{-1}{7}\text{cm})$
4. $(\frac{+20}{7}\text{cm},\frac{+1}{7}\text{cm})$

Q. A rod of length $10\text{cm}$ lies along the principal axis of a concave mirror of focal length $10\text{cm}$ in such a way that its end close to the pole is $20\text{cm}$ away from the mirror. The length of the image is

1. $10\text{cm}$
2. $15\text{cm}$
3. $2.5\text{cm}$
4. $5\text{cm}$

Q. An object is placed at a distance of $40\text{cm}$ from a concave mirror of focal length $15\text{cm}$. If the object is displaced through a distance of $20\text{cm}$ towards the mirror, the displacement of the image will be :

1. $30\text{cm}$ away from the mirror
2. $36\text{cm}$ away from the mirror
3. $36\text{cm}$ towards the mirror
4. $30\text{cm}$ towards the mirror
   

Q.

In which of the following cases, the rays after reflection from a concave mirror diverge:

1. When the object is place at infinity

2. When the object is placed between center of curvature and the focus

3. When the object is placed between focus and the pole

4. Never. Concave mirror is a converging mirror.

Q. An object $\left(ABED\right)$ is placed in front of a concave mirror beyond the centre of curvature $\left(C\right)$ as shown in the figure. The shape of image will be :
(Consider $DE$ and $AB$ as extended objects)

1. 
2. 
3. 
4. 

Q. An object is placed at a distance of $30\text{cm}$ from a concave mirror and its real image is formed at a distance of $30\text{cm}$ from the mirror. The focal length of the mirror is

1. $15\text{cm}$
2. $45\text{cm}$
3. $30\text{cm}$
4. $20\text{cm}$

Q. The focal length of a concave mirror is $30cm$. Find the distance of the object in front of the mirror, so that the image is three times the size of the object.

1. $40cm,20cm$
2. $30cm,50cm$
3. $60cm,80cm$
4. $25cm,15cm$

Q. An object of length 2.5 cm is placed at a distance of 1.5 f from a concave mirror where f is the magnitude of the focal length of the mirror. The length of the object is perpendicular to the principal axis. The length of the image is

1. 5 cm, erect
2. 10 cm, erect
3. 15 cm, erect
4. 5 cm, inverted

Q. An object is placed at a distance of $40\text{cm}$ from a concave mirror of focal length $15\text{cm}$. If the object is displaced through a distance of $20\text{cm}$ towards the mirror, the displacement of the image will be :

1. $30\text{cm}$ away from the mirror
2. $36\text{cm}$ away from the mirror
3. $36\text{cm}$ towards the mirror
4. $30\text{cm}$ towards the mirror
   

Q. The figure shows two incident rays $A$ and $B$ being reflected by a mirror as $A^{\prime }$ and $B^{\prime }$. The mirror is a

1. plane mirror
2. convex mirror
3. concave mirror
4. convex mirror or a concave mirror

Q. An infinitely long rod lies along the axis of a concave mirror of focal length f. The near end of the rod is at a distance u > f from the mirror. Its image will have a length

1. $\frac{uf}{u-f}$
2. $\frac{uf}{u+f}$
3. $\frac{f^2}{u+f}$
4. $\frac{f^2}{u-f}$

Q. A point object $S$ is placed midway between two concave mirrors having equal focal length $f$ as shown in the figure. Find the possible value(s) of $d$ for which only one image is formed of the object.

1. $d=2f,4f$
2. $d=2f,3f$
3. $d=3f,4f$
4. $d=2f$

Q. An object placed in front of a concave mirror of focal length $0.15\text{m}$ produces a virtual image which is twice the size of the object. The position of the object from the mirror as per sign convention is

1. $-6.5\text{cm}$
2. $+6.5\text{cm}$
3. $-7.5\text{cm}$
4. $+7.5\text{cm}$

Q. A concave mirror of focal length $f$ produces an image $n$ times the size of the object. If the image is real, then the distance of the object from the mirror is :

1. $(n-1)f$
2. $\left(\frac{n+1}{n}\right)f$
3. $\left(\frac{n-1}{n}\right)f$
4. $(n+1)f$

Q. The figure shows two incident rays $A$ and $B$ being reflected by a mirror as $A^{\prime }$ and $B^{\prime }$. The mirror is a

1. plane mirror
2. convex mirror
3. concave mirror
4. convex mirror or a concave mirror

Q. Two objects A and B when placed one after another infront of a concave mirror of focal length 10 cm from images of same size. Size of object A is four times that of B. If object A is placed at a distance of 50 cm from the mirror, what should be the distance of B from the mirror

1. 10 cm
2. 20 cm
3. 30 cm
4. 40 cm

Q. An object is placed at a distance of 60 cm from a convex mirror, which forms its image at a distance 30 cm, behind the mirror. The height of the object is 10 cm, find the focal length of the mirror and height of the image.

1. 60 cm, 5 cm
2. -60 cm, 5 cm
3. 60 cm, 10 cm
4. 40 cm, 5 cm

Q. A point object is placed at a distance of 10 cm and its real image is formed at a distance of 20 cm from a concave mirror. If the object is moved by 0.1 cm towards the mirror, the image will shift by about

1. 0.4 cm away from the mirror
2. 0.4 cm towards the mirror
3. 0.8 away from the mirror
4. 0.8 cm towards the mirror

Q. An object is placed $40\text{cm}$ infront of a concave mirror of focal length $20\text{cm}$. The image formed is

1. real, inverted and of same size
2. real, inverted and smaller in size
3. virtual, erect and larger in size
4. virtual, erect and smaller in size