15. Two cars 1&2 starting from rest are moving with speeds v, and v₂ m/s (v, > v₂). Car 2 is ahead of car 'I' by 's' metres when the driver of car '1' sees car '2'. What mini- mum retardation should be given to car 'I' to avoid collision [AIEEE 2002] .
1)v1-v2/s
2)v1+v2/s
3)(v1+v2)^2/2s
4)(v1-v2)^2/2s
no scam
for correct answer I will mark as brainlist
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