Question # The motion of a particle along a straight line is

# The motion of a particle along a straight line is

A described by equation ( x=8+12 t-t^{3}, ) where ( x ) is in metre and ( t ) in second. The retardation of the particle when its velocity becomes zero is

Solution

( x=8+12 t-t^{3} )

( v=12-3 t^{2} )

( 0=12-3 t^{2} )

( t^{2}=3 t^{2} )

( t^{2}=4 )

( t=2 )

( a=-6 t )

( a=-6 times 2 )

( =-12 m / 3^{2} )