The pair of physical quantities that are scalar only are ?

Answer Details

Scalar physical quantities are those that can be described only by their magnitude, without specifying any direction. For example, mass, temperature, and speed are scalar quantities.
Out of the given options, the pair of physical quantities that are scalar only are volume and area. Both of these quantities can be described only by their magnitude, without any reference to direction.
On the other hand, moment and momentum, length and displacement, and impulse and time are all vector quantities. These physical quantities have both magnitude and direction.
Moment is the product of a force and its perpendicular distance from a reference point. Momentum is the product of an object's mass and velocity. Both of these physical quantities have direction and magnitude.
Length and displacement are also vector quantities. Displacement is the change in position of an object from one point to another, and it has both magnitude and direction. Length, on the other hand, is the distance between two points, and it too has both magnitude and direction.
Impulse and time are also not scalar quantities. Impulse is the product of force and time, and it has both magnitude and direction. Time, although it is a one-dimensional quantity, does not have direction but it has magnitude.
Therefore, the correct answer is "volume and area". These are the only scalar physical quantities out of the given options.