₹10,000 is invested at 10% interest per year, for 2 years

₹10,000 is invested at 10% interest per year, for 2 years. Vikram says both years earn the same amount of interest, so the 2-year total is just double the first year's interest. His friend Ira says the second year earns slightly more, because interest is calculated on the growing amount, not just the original ₹10,000. Who is right?