Problem

A particle is moving in

x

y

plane. Its initial velocity and acceleration are

\mathbf{u} = (4\hat{i} + 8\hat{j}) \text{ m/s}

and

\mathbf{a} = (2\hat{i} - 4\hat{j}) \text{ m/s}^2

. Find Initial coordinates of particle are

(4\text{m}, 10\text{m})

. (a) the time when the particle will cross the

x

-axis. (b)

x

-coordinate of particle at this instant. (c) velocity of the particle at this instant.