The resultant of two forces 3P and 2P is R. if the first is doubled the resultant is also doubled. Then angle between two forces.

Explanation

To solve the problem, we need to find the angle between two forces, 3P and 2P, given that when the first force is doubled, the resultant is also doubled. We will follow these steps:

### Step 1: Write the expression for the resultant of two forces
The resultant \( R \) of two forces \( A \) and \( B \) can be expressed using the formula:
\[ R = \sqrt{A^2 + B^2 + 2AB \cos \theta} \]
where \( A = 3P \) and \( B = 2P \).
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