Concept:A vector quantity has both magnitude and direction, while a scalar quantity has only magnitude.
Temperature gradient is the only vector among the options.
Explanation:Temperature gradient is the rate of change of temperature with distance along a chosen direction.
It is expressed as
Tg=ΔxΔT=LT2−T1.
This quantity points from the hot region toward the cold region, so it has a definite direction.
Because it possesses both magnitude and a specific direction, temperature gradient is a vector quantity.
Mass has only magnitude and no direction, hence it is scalar.
Work is a scalar product of force and displacement, so it is also scalar.
Time has magnitude only and is a fundamental scalar quantity.
Therefore, the correct option is the temperature gradient.
Answer:A. Temperature gradient