State any two methods by which ordinary light can be polarised.

Explanation

To answer the question about the methods by which ordinary light can be polarized, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Polarization**:
- Polarization is the process by which the vibrations of light waves are restricted to a particular direction. Ordinary light, such as sunlight, consists of waves vibrating in multiple directions.

2. **Method 1: Polarization by Double Refraction**:
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