Image Formation in Concave Mirror

Q.

An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror with a radius of curvature of 30 cm. Find the position of the image, its nature, and size.

Q. 32.Calculate the focal lenth of spherical mirror from the following observations.object distance u=(50.1+-0.5)cm and image distance v=(20.1+-0.2)cm.

Q.

The image formed by a concave mirror is observed to be virtual, erect, and larger than the object. Where should be the position of the object?

1. Between the principal focus and the center of curvature

2. At the center of curvature

3. Beyond the center of curvature

4. Between the pole of the mirror and its principal focus.

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. A virtual image is formed if the object is placed between focus and the pole of a concave mirror.

1. False
2. True

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 is placed at a distance of $10cm$ from a convex mirror of a focal length of $15cm$. Find the position and nature of the image.

Q.

Draw the ray diagrams for the following positions of an object in front of a concave mirror.

Between centre of curvature and focus.

Q.

The graph shows variation of v with change in u for a mirror. Points plotted above the point P on the curve are for values of v [CPMT 1987]

1. Smaller then f

2. Smaller then 2f

3. Larger then 2f

4. Larger than f

Q. A concave mirror of focal length 15 cm forms an image having twice the linear dimensions of the object. The position of the object when the image is virtual will be

1. 22.5 cm
2. 7.5 cm
3. 30 cm
4. 45 cm

Q. A concave mirror has a focal length of 20 cm. There are three points P, Q, and R at a distance of 10 cm, 20 cm and 30 cm from the pole of the mirror. At what point should the object be kept so that the size of its image is larger than the size of the object itself.

1. P & Q
2. Q & R
3. R & P
4. P, Q & R

Q.

A thin rod of length f/3 lies along the axis of a concave mirror of focal length f One end of its magnified image touches an end of the rod. The length of the image is
[MP PET 1995]

1. $f$
2. $\frac{1}{2}f$
3. $2f$
4. $\frac{1}{4}f$

Q. The minimum distance between the object and its real image for concave mirror is

1. f
2. 2f
3. 4f
4. Zero

Q. A concave mirror forms a real image of a point source lying on the optical axis at a distance of $50\text{cm}$ from the mirror. The focal length of the mirror is $25\text{cm}$. The mirror is cut into two equal parts and each of the two halves are rotated about $S$ by ${90}^{\circ }$, one in anticlockwise and other in clockwise with reference to the original position, then the distance between the two images formed by each part will be

1. $3\text{cm}$
2. $2\text{cm}$
3. $1\text{cm}$
4. $0\text{cm}$

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. A convex mirror has a focal length $f$. A real object is placed in front of it, at a distance $f$ from the pole. At what distance from the pole the image will be formed :

1. Infinity
2. $f$
3. $\frac{f}{2}$
4. $2f$

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

Q.

Which of the following graphs is the magnification of a real image against the distance from the focus of a concave mirror

1. 
2. 
3. 
4. 

Q. A spherical mirror having focal length $f=-25\text{cm}$ is used to obtain an image which is of the same size as that of the object. What should be the object distance $\left(u\right)$ as per sign convention?

1. $u=+25\text{cm}$
2. $u=-30\text{cm}$
3. $u=-25\text{cm}$
4. $u=-50\text{cm}$

Q. Find the distance between object $\left(O\right)$ and final image formed after two successive reflections. Take the first reflection on mirror $M_1$ having radius of curvature $20\text{cm}$

1. $20\text{cm}$
2. $15\text{cm}$
3. $40\text{cm}$
4. $35\text{cm}$

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. 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.

A concave mirror of focal length 100 cm is used to obtain the image of the

sun which subtends an angle of 30⁰ The diameter of the image of the sun

will be

1. 1.74 cm

2. 0.87 cm

3. 0.435 cm

4. 100 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. A concave spherical mirror with a real object will always form a real image.

1. Always True
2. Always False
3. May be True in some cases
4. Data Insufficient

Q. In which case, the nature of the image will be virtual, erect and enlarged ?

1. 
2. 
3. 
4. 

Q. A concave mirror forms a real image of a point source lying on the optical axis at a distance of $50\text{cm}$ from the mirror. The focal length of the mirror is $25\text{cm}$. The mirror is cut into two equal parts and each of the two halves are rotated about $S$ by ${90}^{\circ }$, one in anticlockwise and other in clockwise with reference to the original position, then the distance between the two images formed by each part will be

1. $3\text{cm}$
2. $2\text{cm}$
3. $1\text{cm}$
4. $0\text{cm}$

Q. A gun of mass M fires a bullet of mass m with a horizontal speed V. The gun is fitted with a concave mirror of focal length f facing towards the receding bullet. Find the speed of separation of the bullet and the image just after the gun was fired.

Q. A spherical mirror having focal length $f=-25\text{cm}$ is used to obtain an image which is of the same size as that of the object. What should be the object distance $\left(u\right)$ as per sign convention?

1. $u=+25\text{cm}$
2. $u=-30\text{cm}$
3. $u=-25\text{cm}$
4. $u=-50\text{cm}$

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