Water is being pumped out through a circular pipe whose internal diameter is 7cm. If the flow of water is 12 `cm^3` per second, how many litres of water is being pumped out in one hour ?

Options

A. `1663.2`
B. 1500
C. `1747.6`
D. 2000

Answer

To solve the problem step-by-step, we will follow the given information and perform the necessary calculations.

### Step-by-Step Solution:

1. **Identify the given values:**
- Internal diameter of the pipe = 7 cm
- Flow rate of water = 12 cm³ per second

2. **Calculate the radius of the pipe:**
- Radius (r) = Diameter / 2 = 7 cm / 2 = 3.5 cm

3. **Calculate the volume of water pumped out in one second:**
- The flow rate is already given as 12 cm³ per second. Therefore, the volume of water pumped out in one second = 12 cm³.

4. **Calculate the total volume of water pumped out in one hour:**
- There are 3600 seconds in one hour (60 seconds/minute × 60 minutes/hour).
- Total volume in one hour = Flow rate × Number of seconds in one hour
- Total volume = 12 cm³/second × 3600 seconds = 43200 cm³

5. **Convert the volume from cm³ to liters:**
- We know that 1 liter = 1000 cm³.
- Therefore, to convert cm³ to liters, we divide by 1000.
- Total volume in liters = 43200 cm³ / 1000 = 43.2 liters

### Final Answer:
The total amount of water being pumped out in one hour is **43.2 liters**.