A company has issued 10% Debentures of Face Value of Rs. 5,00,000 as Collateral Security against Rs. 6,00,000, 12% Bank Loan. What amount of total interest will be paid by company for the whole year?

When debentures are issued as collateral security against a bank loan, no interest is payable on these specific collateral debentures because they are secondary security and no cash capital was received directly against them. Interest is paid only on the primary active source, which is the bank loan.
$$\text{Interest on Bank Loan}=6,00,000\times \frac{12}{100}=\text{Rs. }72,000$$
$$\text{Interest on Collateral Debentures}=\text{Rs. }0$$
$$\text{Total Interest Paid}=\text{Rs. }72,000$$