A physical quantity which has a direction:-

Options

A. must be a vector
B. may be a vector
C. must be scalar
D. none of the above

Answer

To solve the question "A physical quantity which has a direction," we need to identify the type of physical quantity being referred to. Here’s a step-by-step solution:

### Step 1: Understand the Definition of Physical Quantities
Physical quantities can be classified into two main categories: scalar quantities and vector quantities.

### Step 2: Identify Scalar and Vector Quantities
- **Scalar quantities** are those that have only magnitude (e.g., mass, temperature, speed).
- **Vector quantities** are those that have both magnitude and direction (e.g., force, velocity, displacement).

### Step 3: Analyze the Given Question
The question specifically asks for a physical quantity that has a direction. This indicates that we are looking for a vector quantity.

### Step 4: Conclude the Answer
Since a vector quantity is defined as having both magnitude and direction, the answer to the question is that a physical quantity which has a direction is a **vector**.

### Final Answer
The correct option is **vector**.

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