Magnification

Q.

The magnification produced by a mirror is $-1$. What does it mean?

Q. The magnification produced by a plane mirror is:

1. 1
2. +1/2
3. -1
4. 0

Q.

Relate the image distance (v), object distance(u) , image height(h') and object height(h) for the formula of magnification (M).

1. M = $\frac{h^{\prime }}{h}$ = $\frac{-v}{u}$

2. M = $\frac{h}{h^{\prime }}$ = $\frac{-v}{u}$

3. M = $\frac{h}{h^{\prime }}$ = $\frac{u}{v}$

4. M = $\frac{h}{h^{\prime }}$ = $\frac{v}{u}$

Q.

What is the magnification produced by a mirror when the image formed is half the size of the object?

1. m = 2

2. m = 0.5

3. m = 4

4. m = 0.25

Q. A rod of length 5 cm lies along the principal axis of the concave mirror of focal length 15cm in such a way that the end of the closer to the pole is 30cm away from it .then the length of the image i

Q.

If an object is $3$ cm away from the plane mirror, what is the distance of the image formed from the mirror?

1. Blue

2. Green

3. White

4. Black

Q.

The image of an object is smaller than the object. What can be said about the magnification produced by the mirror?

1. m > 1

2. m < 1

3. m = 1

4. m = 0

Q.

What is meant by magnification ? Write its expression. What is its sign for the (a) real (b) virtual, image ?

Q. Which of the following show the characteristics of the image formed by a concave lens?

1. Images are real
2. Images are inverted
3. None of the above
4. Images are highly magnified

Q. how to find size of image when magnification is not given

Q.

How will the magnitude of magnification change if an object placed at the center of curvature is moved away from the mirror?

1. decreases

2. remains constant

3. increases

4. magnification reaches infinity

Q. The magnitude of the radius of curvature of a convex mirror is 40 cm. Its focal length is:

1. -20 cm
2. 20 cm
3. -80 cm
4. 80 cm

Q. an object is placed at a distance of 5 cm from a concave mirror of radius of curvature 10 cm determine the position and nature of the image

Q. A square loop of wire of side 4 cm is placed 20 cm away from a concave mirror of focal length 8 cm. What is the area enclosed by the image of the wire ?(assume that the center of loop is on the axis of the mirror and the two sides are normal to the mirror)

Q. a object of height 6 cm is placed on the principal axis of a concave mirror of focal length f at a distance of 4f the length of the image will be

Q. The focal lenghth of a concave mirror is f and the distance of the object from the principal focus p . then the ratio of the size of the image to the size of the object is given by ?

Q. What is the quality of image formed if its magnification is zero

Q.

What is the magnification of a plane mirror?

1. 1

2. 0

3. none of these

4. α

Q.

The image of an object is inverted ___

1. when the magnification of the image is positive

2. when the magnification of the image is negative

3. when the magnification of the image is unity

4. when the magnification of the image is zero