linear magnification

A concave mirror of focal length 20 cm forms an image having twice the size of object. For the virtual position of object, the position of object will be at:

• 25 cm

• 40 cm

• 10 cm

• At infinity

If a man’s face is 25 cm in front of concave shaving mirror producing erect image 1.5 times the size of face, focal length of the mirror would be:

• 75 cm

• 25 cm

• 15 cm

• 60 cm

A ray of light is travelling from a rarer medium to a denser medium. While entering the denser medium at the point of incidence, it:

• goes straight into the second medium

• bends towards the normal

• bends away from the normal

• does not enter at all

an air bubble inside water behaves as

• converging lens

• Diverging lens

The line A & B in the ray diagram of figure represent a _______________ lens.

• converging

• Diverging

The d_o will be a _________________ value.

• positive
• negative

Tags

NGSS.HS-PS3-1

In the thin lens equation, do represents 

• Distance of the object from the lens
• Distance of the image from the lens

The d_i for a real image will be a _________________ value

• positive
• negative

The d_i for a virtual image will have a ______ value.

• positive
• negative

Magnification is always positive.

• True
• False