Physical resultant of two or more vectors is a single vector whose effect is same as the combine effect of all the vectors to be added is called:

Explanation

(a) Unit vector: A unit vector is a vector that has a magnitude of 1. It is used to represent direction and is often used in calculations involving vectors. (b) Product vector: The term "product vector" is not commonly used in the context of vector addition. It may refer to specific operations like the cross product or dot product, which involve multiplying vectors in different ways. (c) Component vector: A component vector refers to the individual vectors that make up a resultant vector. It represents the contribution of each vector in a specific direction. (d) Resultant vector: The resultant vector is the single vector that represents the combined effect of two or more vectors. It is obtained by adding or subtracting the individual vectors using vector addition or subtraction. In the context of the question, the correct answer is (d) resultant vector, as it represents the combined effect of all the vectors being added.