1. Suppose a 1000 -kg car collides with a tree. Its speed changes from 6m/s to 0m/s The impulse on the car is (0.5 Points) [4 positive negative

<p> Impulse is defined as the change in momentum of an object when the object is acted upon by a force for an interval of time. The impulse J on an object is the product of the force F acting on the object and the time Δt that the force is acting: J = F*Δt. Here, since the car is coming to a stop, the impulse must be in the direction opposing the initial motion of the car (that is, the force must be a deceleration). This "negative" impulse occurs as a result of the collision with the tree, bringing the car from its initial speed to a standstill. This is why the correct answer is "negative". By its nature, the question asks which direction the impulse is directed. In this sense, "positive" and "negative" do not represent the magnitude of impulse (which would always be positive), but rather its direction. In the case where the velocity changes from positive to negative (car comes to a stop), the impulse would indeed be negative.</p>