11Please help [2]
Koi to solve karo [79]
Ques 1) A boy of height 1.5 m with the eye level at 1.4 m stands before a plane mirror of length 0.75 m fixed on the wall. The height of the lower edge of the mirror above the floor is 0.8 m. Then :-
(a) the boy will see his full image.
(b) the boy can not see his hair.
(c) the boy cannot see his feet.
(d) the boy can see neither his hair nor his feet.
Ques 2) 
An object O is just about to strike a perfectly reflecting inclined plane of inclination 37° .It's velocity is 5 m/sec. Find the velocity of the image.
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UP 0 DOWN 0 0 6
6 Answers
1In Q1, the boy can see his full image.
Reason: For the boy to see a full image of himself, the mirror should be such that it is half his actual height.
Here the mirror is half his actual height, and is placed 0.8 m above ground level. So the mirror is 0.5 m above the boy's height. He can see his head.
The boy's eyes are 0.6 m above bottom of the mirror, so he can see a total range of 0.6 + 0.6 m till the bottom. Since his height from the ground till eyes is 1.4m, hence the boy can't see the bottom 0.2 m.
Hence he cannot see his feet.
1For Q2, give me the frame of reference. Are you asking the velocity of image from an inertial frame of reference, or are you asking the velocity of the image with respect to the object?
If you are asking velocity of the image as viewed from environment (view it as per the image you have drawn), the rate of approach towards the mirror is the same as the rate of the object approaching the mirror. In this case, i am giving you SPEED of the image. So answer is 5 m/s.
If you are asking relative velocity of image w.r.t object, answer is 5√2 m/s.
11Ans is given as 4.8 i + 1.4 j m/s
Nothing is mentioned abt the frame of refernce.