A person standing 1 m in front of a plane mirror approaches the mirror by 40 cm. The new distance between the person and his image in the plane mirror is

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Q: 9 (CDS-I/2015)
A person standing 1 m in front of a plane mirror approaches the mirror by 40 cm. The new distance between the person and his image in the plane mirror is

question_subject: 

Maths

question_exam: 

CDS-I

stats: 

0,20,23,16,20,4,3

keywords: 

{'plane mirror': [0, 0, 0, 7], 'new distance': [0, 0, 0, 1], 'mirror': [0, 0, 0, 1], 'person': [3, 1, 18, 13], 'front': [1, 0, 4, 7], 'image': [0, 1, 3, 23], 'cm': [2, 0, 7, 20]}

Option 1: 60 cm - This option is incorrect because it suggests that the distance between the person and his image in the mirror increases to 60 cm, which is not true. Approaching the mirror would actually decrease the distance between the person and his image.

Option 2: 1-2 m - This option is the correct answer. When the person approaches the mirror by 40 cm, the distance between the person and his image in the mirror will also decrease by 40 cm. Therefore, the new distance will be 1 m - 40 cm = 60 cm.

Option 3: 1-4 m - This option is incorrect because it suggests that the distance between the person and his image in the mirror decreases to 1-4 m, which is not accurate. The correct distance is 60 cm (or 0.6 m), as explained in option 2.

Option 4: 2-0 m - This option is incorrect because it suggests that the distance between the person and his image in the mirror increases to 2-0 m, which is not true. The correct distance is 60 cm (or 0.6 m), as explained in option 2.

In conclusion, when a person standing