Question

6.
When a plane mirror is placed horizontally on level ground at a distance of 60m from the foot of tower,
the top of the tower and its image in the mirror subtend an angle of 90° at the eye. The height of the tower
1S
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a) 30 m
b) 60 m
c) 90 m
d) 120 m​

Answer 1

Answer:

60 m

Explanation:

The angle subtended at the eye by the top of the

tower with respect to the ground os 45 degrees.

This happens when the height of the tower is

equal to tis distance from the eye. The eye is

assumed to be very near to the mirror. (Refer

below figure).

Angle subtended by AB = 90 degrees/2 = 45

degrees.

Therefore, tanθ=60h.Thatis,tan45=60h

.So,h=60m.