Physics Light Class-X

An object is placed 20 cm in front of a plane mirror. The mirror is moved 2 cm towards the object. The distance between the positions of the original and final images seen in the mirror is:

• 2 cm

• 4 cm

• 10 cm

• 22 cm

A ray of light that strikes a plane mirror PQ at an angle of incidence of 30^o, is reflected from the plane mirror and then strikes a second plane mirror QR placed at right angles to the first mirror. The angle of reflection at the second mirror is:

• 30°

• 45°

• 60°

• 90°

An object is placed at 100 mm in front of a concave mirror which produces an upright image (erect image). The radius of curvature of the mirror is:

• Less than 100 mm

• Between 100 mm and 200 mm

• Exactly 200 mm

• More than 200 mm

Which position of the object will produce a magnified virtual image, if a concave mirror of focal length 15 cm is being used?

• 10 cm

• 20 cm

• 30 cm

• 35 cm

A concave mirror produces a magnification of +4. The object is placed:

• At the focus

• Between focus and centre of curvature

• Between focus and pole

• Beyond the centre of curvature

A ray of light is travelling in a direction perpendicular to the boundary of a parallel glass slab. The ray of light:

• Is refracted towards the normal

• Is refracted away from the normal

• Is reflected along the same path

• Does not get refracted

A lens of focal length 12 cm forms an erect image, three times the size of the object. The distance between the object and image is:

• 8 cm

• 16 cm

• 24 cm

• 36 cm