(a) When the oscillating electric and magnetic fields are along the X- and Y-direction respectively
(i) point out the direction of propagation of electromagnetic wave,
(ii) express the velocity of propagation in terms of the amplitudes of the oscillating electric and magnetic fields.
(b) How do you show that an electromagnetic wave carries energy and momentum?

Explanation

### Step-by-Step Solution

#### Part (a)

**(i) Direction of Propagation of Electromagnetic Wave:**

1. **Identify the Orientation of Electric and Magnetic Fields:**
- Given that the electric field \( \vec{E} \) is along the X-direction and the magnetic field \( \vec{B} \) is along the Y-direction.
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