The displacement of an object as a function of time is given by x = 4t - 2t^2 meters. Velocity of an object is defined as rate of change of its displacement w.r.t. time(dx/dt) Where x displacement along x-axis.
15. What is the magnitude of acceleration of the object at time t = 2 sec?
(A) 2 m/s2 (B) 4 m/s? (C) 6 m/s (D) None of the above
16. The distance travelled by the object in time interval 0 to 3 sec is
(A) 10 m (B) 6 m (C) (D) none of these
Answers
Answer:
Velocity is given as time derivative of displacement whereas acceleration is time derivative of velocity
So velocity v=dx/dt=A+2Bt
Acceleration a=dv/dt=0+2B=2B
15.Acceleration (a) is the change in velocity (Δv) over the change in time (Δt), represented by the equation a = Δv/Δt. This allows you to measure how fast velocity changes in meters per second squared (m/s^2). Acceleration is also a vector quantity, so it includes both magnitude and direction.
16. Though the moving object comes back to its initial position the distance travelled is not zero.
Displacement is calculated on the basis of initial and final position. If initial and final position are same, displacement is zero. But distance is the total distance covered from initial to final position. So, it cannot be zero in this case.