Which one of the following is a vector

A vector quantity is defined by having both magnitude and direction [t1][t2]. Kinetic energy is a scalar quantity because it represents the 'quantity of motion' without directional information [t2][t6]. Pressure is defined as force per unit area; while force is a vector, pressure itself is a scalar quantity in fluid mechanics as it acts equally in all directions at a point [t1][t2]. Density, defined as mass per unit volume, is also a scalar quantity [c4][t1]. However, momentum is a vector quantity because it is the product of mass and velocity (a vector) [t6][t8]. According to Newton's Second Law, the rate of change of momentum is equal to the net force acting on an object. Since force is a vector and momentum is a vector, the rate of change of momentum (dp/dt) must also be a vector quantity [t2][t6].

Sources

1. [1] https://www.sciencedirect.com/topics/engineering/scalar-quantity
2. [2] https://www.grc.nasa.gov/www/k-12/airplane/vectors.html
3. [3] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 9: The Amazing World of Solutes, Solvents, and Solutions > How do scientists define density? > p. 140