Tag: physics

Questions Related to physics

Which of the following mirrors is used to concentrate light on a given spot?

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. concave mirror

  2. convex mirror

  3. plane mirror

  4. both (B) and (C)

Show answer
Correct Option: A
Explanation:

concave mirror focuses a beam of light from infinity at a point

The mirror used in search lights is.

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. concave

  2. convex

  3. plane

  4. convex lens

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Correct Option: A
Explanation:

The mirror used in search lights is a concave mirror

Concave mirrors are used in :

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. reflecting telescopes

  2. magic-lanterns

  3. cinema projectors

  4. all the above

Show answer
Correct Option: D
Explanation:

All the above mentioned optical objects use  concave mirrors.

Shaving mirrors are :

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. convex mirrors

  2. concave mirrors

  3. plane mirrors

  4. dangerous mirrors

Show answer
Correct Option: B
Explanation:

Shaving mirrors need to be concave mirrors

The mirror used by dentists to concentrate light on the tooth to be examined is a ________ mirror.

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. concave

  2. plane or concave

  3. convex

  4. plane

Show answer
Correct Option: A
Explanation:

The mirror used by dentists to concentrate light on the tooth to be examined is a concave mirror.

Dentist's mirror is ...........

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. Concave mirror

  2. Convex mirror

  3. Plane mirror

  4. Convex lens

Show answer
Correct Option: A
Explanation:

$ \bf{Concave\ mirrors} $ are used by dentists because at a short range (object distances less than the focal length of the mirror) they produce enlarged, erect and virtual images. It is useful to have a magnified image of a tooth when repairing cavities, cracks, or other abnormalities.

Hence, the correct answer is OPTION A.

Name the type of mirror used as a shaving mirror

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. Concave mirror

  2. Convex mirror

  3. Plane mirror

  4. None of the above

Show answer
Correct Option: A
Explanation:
Concave mirror is used as shaving mirror. This is because it produces a virtual, erect and magnified image of our face when held in front of the face at a distance less than its focal length thus, allowing us to observe our face closely.

Hence, the correct answer is OPTION A. 

Fill in the blank:

A convex mirror is used as rear view mirror in auto mobiles as it covers ______ area behind the driver.

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. wide

  2. narrow

  3. neither A nor B

  4. very narrow

Show answer
Correct Option: A
Explanation:

Convex mirrors produces virtual, erect image to cover wider area, so that drives able to see large area.

Use of concave mirrors:

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. for examining internal parts of ear, nose, mouth by physicians

  2. to focus sunlight to produce heat in solar furnaces

  3. as reflectors in headlights of vehicles, torch light to produce strong parallel beam of light

  4. all of the above

Show answer
Correct Option: D
Explanation:

Concave mirrors help to produce large image helps doctors to examine body parts and also are used to auto mobile mechanics to produce strong parallel beam of light during night. Concave mirrors are used to focus sunlight to produce heat from solar furnaces.

Mirror used in solar furnace:

physics reflection of light at curved surfaces uses of curved mirrors uses of spherical mirror uses of spherical mirrors

  1. Concave mirror

  2. Convex mirror

  3. Parabolic mirror

  4. Bi concave mirror

Show answer
Correct Option: A
Explanation:

Concave mirrors are used in solar furnaces, because concave mirrors are the only type of mirror that reflects light in toward a single focal point