A body falling for 2 seconds covers a distance S equal to that covered in next second. Taking g=10m/s2,S=
If U is the initial velocity then distance covered by it 2 sec.
S=ut+12at2=u×2+12×10×4=2u+20 ..,(i)
Now distance covered by it in 3rd sec.
S3rd=u+g2(2×3−1)10=u+25 ....(ii)
From(i) and (ii),2u+20=u+25 ⇒ u=5
∴S=2 × 5+20=30 m.