Question Detail
Question
An object starts from rest at the origin and moves along the x axis with a constant acceleration of 4 m/s². Its average velocity as it goes from x = 2 m to x = 8 m is:
Correct Answer
Option C is the correct answer.
Detailed Explanation
First find the velocities at x=2 m and x=8 m. Using v² = u² + 2as, with u=0 at origin, but here we start from rest at origin, so at any position x, v = √(2ax). At x=2, v₁ = √(2×4×2) = √16 = 4 m/s. At x=8, v₂ = √(2×4×8) = √64 = 8 m/s. For constant acceleration, average velocity = (v₁ + v₂)/2 = (4+8)/2 = 6 m/s.
Hint
For constant acceleration, the average velocity is the mean of the initial and final velocities over the interval.