Pendulum bob of mass m connected to a string of length l is made to whirl around in a vertical circle . Maximum speed of bob is found to be double of the minimum speed . Calculate tension in the thread when velocity of the bob is directed vertically downward .

Explanation

To solve the problem, we need to calculate the tension in the string when the pendulum bob is at the lowest point of its circular path, moving vertically downward. We know that the maximum speed of the bob is double the minimum speed. Let's denote the minimum speed as \( v_{\text{min}} \) and the maximum speed as \( v_{\text{max}} = 2v_{\text{min}} \).

### Step 1: Establish the relationship between maximum and minimum speeds
Given:
\[ v_{\text{max}} = 2v_{\text{min}} \]

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