A freely suspended short magnet makes 20 oscillations per minute in the earth's horizontal magnetic field of `40 mu T`. Another short magnet of moment `1.6 A m^(2)` is now placed at 20 cm east pointing its north pole towards north. Find the new number of oscillations per minute.

Explanation

To solve the problem step by step, we will follow the concepts of magnetic fields and oscillations of a magnet in a magnetic field.

### Step 1: Understand the Given Information
We know:
- The initial frequency of oscillation (f1) = 20 oscillations per minute.
- The Earth's horizontal magnetic field (B1) = 40 µT (microtesla).
- The magnetic moment (m) of the second magnet = 1.6 A m².
- The distance (d) from the second magnet to the first magnet = 20 cm = 0.2 m.
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