Final answer:
The velocity of the cart at time t=5 s is 4.5 m/s. After 5 seconds, the cart will continue to accelerate down the ramp with a constant acceleration of 0.5 m/s2 in the x-direction, assuming it does not leave the ramp.
Step-by-step explanation:
Given the information that a small cart is rolling freely on an inclined ramp with a constant acceleration of 0.5 m/s2 in the x-direction and an initial velocity of 2.0 m/s in the +x-direction at time t=0, we can describe the motion of the cart at time t>5 s. The cart's velocity at any time t can be calculated using the equation v = v0 + at, where v is the velocity at time t, v0 is the initial velocity, a is the acceleration, and t is the time.
Using this equation, the velocity of the cart at time t=5 s would be:
v = 2.0 m/s + (0.5 m/s2 × 5 s) = 2.0 m/s + 2.5 m/s = 4.5 m/s
Since the cart never leaves the ramp and there are no forces acting in the horizontal direction other than gravity and the resultant acceleration, the motion of the cart after t>5 s would involve it continuing to accelerate down the ramp at a constant acceleration of 0.5 m/s2.