1. A body starts from rest, acceleration 4 m/s². Distance in 3rd second is:
- 10 m
- 12 m
- 14 m
- 16 m
Show answer and explanation
Answer: (A) 10 m
Distance in the nth second: Sₙ = u + a(2n−1)/2. With u = 0, a = 4 m/s² and n = 3: Sₙ = 0 + 4(5)/2 = 10 m.
Quick tip: Sₙ = u + a(2n−1)/2. Very frequently asked in NEET.
NCERT Class 11, Chapter 3, page 44