Physics
The figure shows the image of a clock as seen in the plane mirror. The correct time is :
- 4:30
- 6:30
- 2:30
- 3:30
Answer
2:30
Reason — As the mirror image of the clock shows that hour hand is pointing slightly past 9 and minute hand at 6 (i.e., 30 minutes) so the mirror image shows 9:30. Since a plane mirror always produces laterally inverted images so in this case the hour hand should actually point slightly past 2 and minute hand will suffer no inversion due to symmetry so the clock will show 2:30.
Related Questions
The type of mirror used as a shaving mirror in daily life is :
- plane mirror
- convex mirror
- concave mirror
- parabolic mirror
Which mirror always forms a diminished image for all positions of the object placed in front of it ?
- plane mirror
- convex mirror
- concave mirror
- parabolic mirror
We use a concave polished metallic surface as a reflector in a torch to obtain a parallel beam of light. The position of the bulb is :
- at the centre of curvature of the reflector.
- at the focus of the reflector
- between the focus and centre of curvature of the reflector
- can be any of the above options
Assertion (A) : For a ray of light incident at an angle of incidence i = 0°, angle of reflection is r = 0°.
Reason (R) : The angle of incidence i is equal to angle of reflection r.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false