Kiran swims in a 90 m long pool. He covers 360 m in two minutes by swimming from one end to the other and back along the same straight path, twice. Find the average velocity of Kiran.

Options

A. `4 ms^(-1)`
B. `5 ms^(-1`
C. `3 ms^(-1)`
D. `0 ms^(-1)`

Answer

To find the average velocity of Kiran swimming in a 90 m long pool, we can follow these steps:

### Step 1: Determine the total distance covered by Kiran.
Kiran swims from one end of the pool to the other and back, twice. The length of the pool is 90 m.

- Distance for one round trip (to one end and back) = 90 m + 90 m = 180 m.
- Since Kiran swims this round trip twice, the total distance covered is:
\[ \text{Total Distance} = 180 \text{ m} \times 2 = 360 \text{ m} \]

### Step 2: Calculate the total time taken.
Kiran takes 2 minutes to cover the total distance of 360 m.

- Total time taken = 2 minutes.

### Step 3: Convert the total time into seconds.
Since average velocity is typically expressed in meters per second (m/s), we need to convert the time from minutes to seconds.

- Conversion: 1 minute = 60 seconds.
- Therefore, 2 minutes = \(2 \times 60 = 120\) seconds.

### Step 4: Calculate the average velocity.
Average velocity is defined as the total displacement divided by the total time taken. However, since Kiran swims back and forth, the total displacement is zero (he ends up at the starting point).

- Total displacement = 0 m (since he returns to the starting point).
- Total time = 120 seconds.

Using the formula for average velocity:
\[ \text{Average Velocity} = \frac{\text{Total Displacement}}{\text{Total Time}} = \frac{0 \text{ m}}{120 \text{ s}} = 0 \text{ m/s} \]

### Conclusion
The average velocity of Kiran is **0 m/s**.

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