Physics - Study Mode

[#131] Convex mirror is generally used in ________
Correct Answer

(D) Rear view mirror

Explanation

Solution: Convex mirror is generally used in rear view mirror.

[#132] In total internal reflection, the light travel from
Correct Answer

(B) Denser to rarer medium and it occurs with no loss of intensity

Explanation

Solution: For total internal reflection to occur the light must travel from a dense medium to a less dense medium (e.g. glass to air or water to air). As the angle of incidence increases so does the angle of refraction.

[#133] Convex mirrors are used as a rear view mirror in motor cycles because
Correct Answer

(C) It forms smaller image as compared with object

Explanation

Solution: We use convex mirror as a rear view mirror in the vehicles because convex mirror always forms virtual, erect and diminished images irrespective of distance of the object. A convex mirror enables a driver to view large area of the traffic behind him. Convex mirror forms very small image than the object.We use convex mirror as a rear view mirror in the vehicles because convex mirror always forms virtual, erect and diminished images irrespective of distance of the object. A convex mirror enables a driver to view large area of the traffic behind him. Convex mirror forms very small image than the object.

[#134] A convex mirror of focal length f (in air) is immersed in a liquid (u=4/3). The focal length of the mirror in the liquid will be :
Correct Answer

(A) F

Explanation

Solution: Mirrors, spherical or otherwise are based on the laws of reflection. That behavior is not affected by the medium in which the light travels, so the mirror's focal length would be no different in air or any other medium.

[#135] The phenomenon which causes mirage is
Correct Answer

(D) Total internal reflection

Explanation

Solution: Mirage is a phenomenon due to total internal reflection of light. It happens when the light goes from optically denser medium (cool air) to rarer medium (hot air) and angle of incidence is equal to or greater than the critical angle resulting total internal reflection at the interface of the two mediums.