Question:

A particle moves along a straight line such that its displacement at any time t is given by $s = (t^3-6t^2+3t+4)$ metres. The velocity when the acceleration is zero is

Updated On: May 2, 2024
  • 3 m/s
  • 42 m/s
  • -9 m/s
  • -15 m/s
Hide Solution
collegedunia
Verified By Collegedunia

The Correct Option is C

Solution and Explanation

Displacement (s) $t^3-6t^2+3t+4$ metres.
velocity (v) $=\frac{ds}{dt} = 3t^2 - 12t + 3 $
acceleration (a) $ =\frac{dv}{dt} = 6t - 12 $
When a = 0, we get t = 2 seconds.
Therefore velocity when the acceleration is zero
$(v) \, \, = 3 \times (2)^2 -(12 \times 2) + 3 = - 9\, m/s.$
Was this answer helpful?
1
0

Concepts Used:

Motion in a straight line

The motion in a straight line is an object changes its position with respect to its surroundings with time, then it is called in motion. It is a change in the position of an object over time. It is nothing but linear motion. 

Types of Linear Motion:

Linear motion is also known as the Rectilinear Motion which are of two types:

  1. Uniform linear motion with constant velocity or zero acceleration: If a body travels in a straight line by covering an equal amount of distance in an equal interval of time then it is said to have uniform motion.
  2. Non-Uniform linear motion with variable velocity or non-zero acceleration: Not like the uniform acceleration, the body is said to have a non-uniform motion when the velocity of a body changes by unequal amounts in equal intervals of time. The rate of change of its velocity changes at different points of time during its movement.