Question

An object is moving along x-axis in such a way that its displacement is given by x = 30 + 20t^2. Find the velocity at t=2s.

Answer 1

Answer:

The displacement is given as: y = ut + 12at2 where, u is the initial velocity and a is the accelerationComparing with given expression: y = - 5t + 6t2 + ...

Answer 2

Answer:

An object is moving along x axis in such a way that its displacement is given by :

x= 30+ 20t^2x=30+20t 2

Where x is in meters and t is in seconds

At initial position, t = 0

x = 30 meters

Velocity,

\begin{gathered}v=\dfrac{dx}{dt}\\\\v=\dfrac{d(30+ 20t^2)}{dt}\\\\v=40t\end{gathered}

v= dtdx

v= dt d(30+20t 2 )

v=40t

At t = 0 s

Velocity, v = 0

Acceleration,

\begin{gathered}a=\dfrac{dv}{dt}\\\\a=\dfrac{d(40t)}{dt}\\\\a=40\ m/s^2\end{gathered}

a= dtdv

a= dt d(40t)

a=40 m/s 2