Determining Force & Direction of 6 kg Particle's Motion

[soul5]

Homework Statement

The velocity of a 6 kg particle is given by v = (5ti + 4t2j ) m/s, with time t in seconds. At the instant the net force on the particle has a magnitude of 43 N, what are the direction (relative to the positive direction of the x axis) of (a) the net force and (b) the particle's direction of travel?

Homework Equations

F= ma

The Attempt at a Solution

I don't know what to do can someone give me a hint?

 

[Gear300]

If you're familiar with momentum, you'll notice that the rate of change of momentum is force (or you could simply note that the rate of change of velocity is acceleration). Just derive the acceleration vector from the velocity vector.