Question

1. the position of a particles moving on a straight line is given by X =12 + 18t + 9t^2meter
(a) find the instantaneous veloctiy at
t=5s [dx/dt=v]

Answer 1

Answer:

v = 108 m/s.

Explanation:

Given that,

The position of a particle moving on a straight line is given by :

$X =12 + 18t + 9t^2$

We need to find the instantaneous velocity at  t=5s.

Velocity, $v=\dfrac{dX}{dt}$

So,

$v=\dfrac{d(12 + 18t + 9t^2)}{dt}\\\\=18+18t$

Instantaneous velocity at t = 5 s will be :

v = 18+18t

v = 18+18(5)

= 18 + 90

= 108 m/s

So, the instantaneous veloctiy at  t=5s is 108 m/s.