Question

Which of the following required two or more directional aspects to define itself?
1. Scalar quantity
2. Vector quantity
3. Tensor quantity
4. None of the above

Answer 1

Correct Answer - Option 3 : Tensor quantity

Explanation:

Tensor quantity:

• Some physical quantities having no proper direction but show different values in different directions.
• Tensors are those which possess magnitude but require two or more directional aspects to specify completely.
• The number of directions required to fully describe a tensor is known as the order of the tensor.
• A scalar quantity is a zero-order tensor and a vector quantity is 1st order tensor and so on.
•  Example: Moment of Inertia, Refractive index, Stress, etc.

Vector quantity: 

• A vector quantity is a quantity that has both a magnitude and a direction and obeys the triangle law of addition or equivalently the parallelogram law of addition. 
• Examples of vector quantities are displacement, weight, force, momentum.

Scalar quantity:

• It has only magnitude and no direction.
• The physical quantities which are specified with the magnitude or size alone are scalar quantities. 
• Examples of scalar quantities are length, speed, work, energy, speed, mass, volume, time, power, electric potential, etc.