Two sinusoidal wave having the same frequency and travelling in the same direction are combined. What is the amplitude of the resultant motion if their amplitudes are 3cm and 4cm and they differ in phase by `pi//2` radian?

Explanation

To find the amplitude of the resultant motion when two sinusoidal waves combine, we can use the formula for the resultant amplitude when the waves have different amplitudes and a phase difference. Here’s a step-by-step solution:

### Step 1: Identify the given values
We have two waves with the following properties:
- Amplitude of the first wave, \( A_1 = 3 \, \text{cm} \)
- Amplitude of the second wave, \( A_2 = 4 \, \text{cm} \)
- Phase difference, \( \phi = \frac{\pi}{2} \, \text{radians} \)

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