The grinding stone of a flour mill is rotating at 600 rad/sec. for this power of 1.2 k watt is used. the effective torque on stone in N–m will be :–

Options

A. 1
B. 2
C. 3
D. 4

Answer

To find the effective torque on the grinding stone of a flour mill, we can use the relationship between power, torque, and angular velocity. The formula we will use is:

\[ P = \tau \cdot \omega \]

Where:
- \( P \) is the power in watts (W)
- \( \tau \) is the torque in Newton-meters (N·m)
- \( \omega \) is the angular velocity in radians per second (rad/s)

### Step-by-Step Solution:

1. **Identify the given values**:
- Power, \( P = 1.2 \, \text{kW} = 1200 \, \text{W} \)
- Angular velocity, \( \omega = 600 \, \text{rad/s} \)

2. **Rearrange the formula to solve for torque**:
\[ \tau = \frac{P}{\omega} \]

3. **Substitute the known values into the equation**:
\[ \tau = \frac{1200 \, \text{W}}{600 \, \text{rad/s}} \]

4. **Perform the calculation**:
\[ \tau = \frac{1200}{600} = 2 \, \text{N·m} \]

5. **Conclusion**:
The effective torque on the stone is \( 2 \, \text{N·m} \).

### Final Answer:
The effective torque on the stone is **2 N·m**.

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