Physics · MOTION IN A STRAIGHT LINE

In the position-time graph shown in the figure, as the time interval \( \Delta t \) centered at \( t = 4\text{ s} \) is reduced from \( 2\text{ s} \) to an infinitesimally small value, the slope of the chord approaches the slope of the tangent at point \( P \). If the position equation is \( x = 0.08 t^3 \), what is the instantaneous velocity at \( t = 4\text{ s} \)?

1. A
   Instantaneous velocity equal to \( 1.92\text{ m s}^{-1} \)
2. B
   Instantaneous acceleration equal to \( 3.84\text{ m s}^{-2} \)
3. C
   Average velocity equal to \( 7.84\text{ m s}^{-1} \)
4. D
   Instantaneous velocity equal to \( 3.84\text{ m s}^{-1} \)