Final answer:
No, a reference point is required to assign angular momentum to a particle because it is necessary to define the perpendicular distance from this point to the particle's line of action, which is essential in the calculation of angular momentum.
Step-by-step explanation:
No, you cannot assign angular momentum to a particle without first defining a reference point. Angular momentum is a measure of the quantity of rotation of a body, which depends on the mass, velocity, and the perpendicular distance from the point to the line of action of the velocity. Without a reference point, you cannot define this perpendicular distance, and thus, you cannot define the angular momentum.
The Law of Conservation of Angular Momentum states that the angular momentum of a system is conserved if there is no net external torque. However, to determine the angular momentum of a particle or system, one must choose a reference point from which to measure this quantity.
In terms of a particle traveling in a straight line, it is possible for there to be points about which the angular momentum is zero. This scenario occurs when the line of motion passes through the chosen origin, making the perpendicular distance zero, and hence the angular momentum zero.