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Q1. What kind of image is formed by a plane mirror?

• Real and inverted
• Real and erect
• Virtual and erect
• Virtual and inverted

Solution

Virtual and erect image is formed by a plane mirror.

Q2. The speed of light in vacuum is

• 3 x 10⁶ m/s
• 3 x 10⁷ m/s
• 3 x 10⁸ m/s
• 3 x 10⁹ m/s

Solution

The speed of light in vacuum is 3 x 10⁸ m/s.

Q3. Dispersion of light by a glass prism takes place because:

• the light of different colors have different intensities.
• the light of different colors have different speeds in a medium.
• the light of different colors have different frequencies.
• the light of different colors have different energies.

Solution

Dispersion of light by a glass prism takes place because the light of different colors have different speeds in a medium. This results in different colours of light being refracted at different angles.

Q4. Angle of reflection is equal to

• None of the above
• Both (a) and (b)
• Angle of incidence
• Optical density

Solution

Angle of reflection is equal to angle of incidence.

Q5. A straight line passing through the geometric centre of the spherical mirror and the focus is called the ____________ of the mirror.

• focal length
• radius of curvature
• principal axis
• aperture

Solution

A straight line passing through the geometric centre of the spherical mirror and the focus is called the principal axis of the mirror.

Q6. The formation of rainbow is an example of _____________of light

• Reflection
• Refraction
• Dispersion
• Transmission

Solution

The formation of rainbow is an example of dispersion of light.

Q7. Power of a lens is measured in

• Centimeters
• Degrees
• Ohms
• Dioptre

Solution

Power of a lens is measured in dioptre.

Q8. A convex lens is :

• thick at the centre and thin at the periphery.
• thick at the centre as well as the periphery.
• thin at the centre and thick at the periphery.
• thin at the centre as well as the periphery.

Solution

A convex lens is thick at the centre and thin at the periphery.

Q9. The depth of a water pond appears to be lesser on account of :

• Reflection of light
• Refraction of light
• Scattering of light
• Dispersion of light

Solution

The depth of water pond appears to be lesser on account of refraction of light.

Q10. What kinds of surfaces reflect light easily?

• Any kind of surface
• Shining, smooth or polished
• Rough, dull or blackened
• None of the above

Solution

Shining, smooth or polished

Q11. Which of the following mirrors can give the full image of a large building?

• Convex mirror
• Concave mirror
• Plane mirror
• All of the above

Solution

A full-length image of a tall building can be seen in a small convex mirror.

Q12. In spectrum obtained with prism which colour is deviated minimum?

• blue
• violet
• red
• green

Solution

Red colour is deviated minimum.

Q13. Which of the following statements is true about a convex mirror?

• It is used as a magnifying glass.
• It is used as side-view mirror of vehicles.
• It is used by dentists to see enlarged image of teeth.
• It is used in headlights of cars.

Solution

Convex mirrors enable the driver to view much larger area than a plane mirror. Hence they are used as a rear view mirror in vehicles to see objects at the backside of the vehicle.

Q14. An object that does not let any light to pass through it is called

• Transparent
• Translucent
• Opaque
• None of the above

Solution

An object that does not let any light to pass through it is called opaque.

Q15. Why convex mirror is used as a side mirror in scooters?

• Because it forms real image
• Because it has large field of view
• Because it forms laterally inverted image
• Because it forms clear image

Solution

A convex mirror is used as a side mirror in scooters because it has large field of view.

Q16. When a white light ray falls on a prism, the ray at its first surface suffers:

• no refraction
• only dispersion
• only deviation
• both deviation and dispersion.

Solution

When a beam of white light reaches the side of a prism, it undergoes refraction  at the boundary of two media - air and glass and it also gets separated into its constituent colours.Hence, on falling on a prism, the ray of light suffers both deviation and dispersion at its first surface.

Q17. A concave lens is called a diverging lens because the incident rays are bent ________.

• Perpendicular
• Outward
• Inward
• In random directions

Solution

A concave lens is called a diverging lens because the incident rays are bent outward.

Q18. For all positions of an object before a convex mirror, the image formed is on _______ side of the mirror.

• The other side
• The same side
• Any side
• None of the above

Solution

The images formed by a convex mirror are always on the other side of the mirror and are virtual.

Q19. Why can't we see a candle flame through a bent hollow pipe?

• Because light travels in straight line
• Because intensity of candle flame is too low
• Because a candle does not radiate in visible range
• None of the above

Solution

We can't see a candle flame through a bent hollow pipe because light travels in straight line only and so it cannot travel through a bent pipe.

Q20. The best choice for a convenience store security mirror would be a

• Plano-concave mirror
• Plane mirror
• Concave mirror
• Convex mirror

Solution

The best choice for a convenience store security mirror would be a convex mirror.

Q21. Which of the following statements is a characteristic of diverging lens?

• The image formed is diminished.
• The image formed is real.
• The image formed is inverted.
• The image can be formed on a screen.

Solution

Diverging or concave lenses form diminished, virtual and erect image.

Q22. The size of the image formed by a plane mirror is

• Smaller than the object
• Same as that of the object
• Larger than the object
• None of the above

Solution

An image formed by a plane mirror is erect and of the same size as the object.

Q23. If the image formed is upright and enlarged as you bring your face towards the mirror, the mirror is ___________.

• Plane
• Concave
• Convex
• Any of the above

Solution

If the image formed is upright and enlarged as you bring your face towards the mirror, the mirror is concave.

Q24. If half part of a convex lens is covered, the focal length ___________ and the intensity of image __________.

• changes, decreases
• changes, remains same
• does not change, decreases
• does not change, remains same

Solution

If half part of a convex lens is covered, the focal length does not change and the intensity of image decreases.

Q25. In order to get a diminished and virtual image, the object can be placed anywhere in front of :

• a concave mirror
• a plane mirror
• a convex mirror
• any mirror

Solution

If the object is placed anywhere in front of a convex mirror, the image formed is diminished and virtual.

Q26. The seven colors present in the rainbow are

• violet, magenta, purple, green, yellow, orange, red
• violet, magenta, purple, cyan, yellow, orange, maroon
• violet, indigo, blue, cyan, yellow, orange, maroon
• violet, indigo, blue, green, yellow, orange, red

Solution

The seven colors present in the rainbow are violet, indigo, blue, green, yellow, orange, red.

Q27. An inverted image can be seen by using a convex mirror:

• when the object is placed just next to the mirror.
• when the object is placed anywhere near the mirror.
• when the object is placed too far from the mirror.
• under no circumstances.

Solution

The image formed by a convex mirror is always virtual and erect irrespective of the position of the object.

Q28. A mirror changes the ________ of light that falls on it.

• Direction
• Optical density
• Speed
• None of the above

Solution

A mirror changes the direction of light that falls on it.

Q29. Which of the following is not a characteristic statement of a plane mirror?

• The magnification of the image formed is 1.
• The image can be formed on a screen
• The image formed is erect.
• The image is formed at the same distance behind the mirror as the object is in front of it.

Solution

Plane mirrors form virtual images which cannot be projected on a screen.

Q30. A wave transfers ________.

• liquid
• matter
• energy
• gas

Solution

A wave transfers energy.

Q31. In which of the following cases, concave mirror is not used?

• Headlights of vehicles
• Torch
• Rearview mirror of vehicles
• Dentist's mirror

Solution

Concave mirror is not used in rearview mirror of vehicles.

Q32. In which of the following cases a convex mirror is not used?

• Sunglasses
• Rear-view mirror in vehicles
• Ceiling dome mirrors for surveillance in shops, offices etc
• Dentist's head mirror

Solution

A concave mirror is used as dentist's head mirror.

Q33. The nature of the image formed by a convex mirror is :

• Real and erect
• Virtual and inverted
• Real and inverted
• Virtual and erect

Solution

The nature of the image formed by a convex mirror is always virtual and erect.

Q34. The working of a lens is based on the phenomenon of ___________ of light.

• reflection     
• refraction     
• dispersion    
• spectrum

Solution

The working of a lens is based on the phenomenon of refraction of light.

Q35. If the image is upright and diminished and it remains upright on moving the mirror away from the face, the mirror is ___________.

• Plane
• Concave
• Convex
• Parabolic

Solution

Convex mirror always forms virtual, upright and diminished image irrespective of the position of the object.

Q36. What type of mirror is likely to be accompanied by a warning that reads; "Objects in mirror are closer than they appear"?

• Plane mirror
• Concave mirror
• Convex mirror
• None of the above

Solution

Convex mirror

Q37. Which is the wrong statement out of the following?

• A concave mirror can give a virtual image.
• A convex mirror can give a virtual image.
• A concave mirror can give a diminished virtual image.
• A convex mirror cannot give a real image.

Solution

A concave mirror can't give the virtual and diminished image. When the object is placed very close to the mirror (between pole and focus), the image formed is virtual, erect and enlarged.

Q38. Jane placed a candle in front of a mirror. The candle which appears behind the mirror is ________ and candle itself is ________.

• object, image
• shadow, image
• image, object
• image, object

Solution

Jane placed a candle in front of a mirror. The candle which appears behind the mirror is image and candle itself is object .

Q39. The glasses used for reading purposes are essentially ______lenses, while those used for seeing distant objects clearly are essentially ______ lenses.

• concave, convex
• convex, concave
• concave, plane
• plane, concave

Solution

The glasses used for reading purposes are essentially convex lenses, while those used for seeing distant objects clearly are essentially concave lenses.

Q40. What effect does a concave mirror have on parallel rays of light falling on it?

• It spreads them out
• It brings them to a point
• It has no effect
• It reflects the light straight back