Which of the following is a scalar quantity ?

Options

A. velocity
B. Acceleration
C. Speed
D. Area

Answer

To determine which of the following is a scalar quantity, let's analyze each option provided: velocity, acceleration, speed, and area.

### Step 1: Understand the definitions of the quantities.
- **Velocity**: This is a vector quantity that has both magnitude and direction. For example, if a car is moving at 60 km/h to the north, both the speed (60 km/h) and the direction (north) are specified.

- **Acceleration**: This is also a vector quantity. It represents the rate of change of velocity and has both magnitude and direction. For instance, if a car's velocity increases from 0 to 60 km/h in 5 seconds, it has a specific direction of acceleration as well.

### Step 2: Analyze the third option, speed.
- **Speed**: This is a scalar quantity. It only has magnitude and does not have a direction. For example, saying a car is traveling at 60 km/h does not specify the direction in which it is moving.

### Step 3: Consider the fourth option, area.
- **Area**: While area is often treated as a scalar quantity because it represents the extent of a surface, it can sometimes be associated with a direction in certain contexts, such as in three-dimensional geometry where it can be defined in relation to a plane (e.g., area in the xy-plane). However, in general usage, area is considered a scalar quantity.

### Conclusion:
Based on the analysis, the only quantity among the options that is definitively a scalar quantity is **speed**.

### Final Answer:
The scalar quantity among the options is **speed**.

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