S.I. unit of velocity is

Options

A. (a) m/s
B. (b) ` m sec^(-1)`
C. (c) `m hr^(-1)`
D. (d) m/hr

Answer

To determine the SI unit of velocity, we can follow these steps:

### Step 1: Understand the definition of velocity
Velocity is defined as the rate of change of displacement with respect to time. Mathematically, it can be expressed as:
\[ \text{Velocity} = \frac{\text{Displacement}}{\text{Time}} \]

### Step 2: Identify the SI unit of displacement
The SI unit of displacement is the meter (m). Displacement refers to the change in position of an object.

### Step 3: Identify the SI unit of time
The SI unit of time is the second (s). Time is a measure of the duration of an event.

### Step 4: Combine the units to find the SI unit of velocity
Since velocity is displacement divided by time, we can combine the units:
\[ \text{SI unit of velocity} = \frac{\text{SI unit of displacement}}{\text{SI unit of time}} = \frac{\text{meters}}{\text{seconds}} = \text{meters per second} \]
This can also be expressed in a different notation as:
\[ \text{meters} \cdot \text{s}^{-1} \]

### Step 5: Conclusion
Thus, the SI unit of velocity is meters per second (m/s).

### Final Answer
The SI unit of velocity is **meters per second (m/s)**.

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