NTA Abhyas JEE Main2020PhysicsMotion in One DimensionPractice
A car accelerates from rest at a constant rate of 2 m s - 2 for some time. Then, it retards at a constant rate of 4 m s - 2 and comes to rest. If the total time for which it remains in motion is 3 s , Then the total distance travelled is
Options
- A2   m
- B3   m
- C4   m
- D6   m
Correct answer
D. 6   m
Step-by-step solution
Using v = u + at or v - u = at , we find that if a → is doubled, t will be halved. If t is the time for accelerations, then t 2 is the time for retardation. Now, t + t 2 = 3 or 3 t 2 = 3 t = 2 s S = 1 2 × 2 × 2 × 2 + 1 2 × 4 × 1 × 1 = 4 + 2 m = 6 m