Answer:
5.266 secs
Step-by-step explanation:
Lets assume ; p(t) = t^-3 + 2^2 + ( 3/2 ) is the particle position along x-axis
time interval [ 0, 4 ]
Average velocity = Displacement / time
= p( b ) - p( a ) / b - a -------- ( 1 )
where a = 0 , b = 4 ( time intervals )
Back to equation 1
Average velocity = [ ( 4^-3 + 4 + (3/2) ) - ( 0 + 4 + (3/2) ) ] / 4
= 3.9 * 10^-3 ----- ( 2 )
Instantaneous velocity = d/dx p(t)
= - 3/t^4 ------ ( 3 )
To determine the time that the instanteous velocity = average velocity
equate equations (2) and (3)
3.9*10^-3 = - 3 / t^4
t^4 = - 3 / ( 3.9 * 10^-3 ) = - 769.231
hence t = = 5.266 secs
we ignore the negative sign because time can not be in the negative