A stone of of mass 0 .25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of `40 rev//min` in a horizontal plane What is the tension in the string ? What is the maximum speed with which the stone can be whirled around If the string can withstand a maximum tension of 200 N ?

Explanation

To solve the problem, we need to find the tension in the string when a stone of mass 0.25 kg is whirled around in a circle of radius 1.5 m at a speed of 40 revolutions per minute (rev/min). We will also determine the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200 N.

### Step 1: Convert the speed from revolutions per minute to meters per second

1. **Calculate the circumference of the circle**:
\[ C = 2 \pi r = 2 \pi \times 1.5 \text{ m} = 3\pi \text{ m} \]
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