1. Use the prism formula for minimum deviation

For a thin prism, the minimum deviation is approximately

$\delta_m \approx (\mu - 1)A$

where:

• $\mu = 1.5$
• $A = 1^\circ$

2. Substitute the values

$\delta_m \approx (1.5 - 1) \times 1^\circ = 0.5^\circ$

3. Match with the given form

The question says the minimum deviation is close to

$\frac{N}{10}$

degrees.

So,

$\frac{N}{10} = 0.5$

Thus,

$N = 5$

4. Final answer

$\boxed{5}$

5. Comparison with stored answer

Stored correct answer = $5$

Our derived answer also equals $5$, so they agree.