Bob of the simple pendulum is at rest at its lowest position , Sharp hit imparts a speed of `sqrt(9gl)` to the pendium bob. Calculate tension of the thread when it makes an angle `60^(@)` with the vertical .

Explanation

To solve the problem of calculating the tension in the thread of a pendulum bob when it makes an angle of \(60^\circ\) with the vertical after being imparted a speed of \(\sqrt{9gl}\), we can follow these steps:

### Step 1: Identify the forces acting on the pendulum bob
At an angle of \(60^\circ\), the forces acting on the bob are:
- The weight of the bob \(mg\) acting downwards.
- The tension \(T\) in the thread acting along the thread towards the pivot.

### Step 2: Resolve the weight into components
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