On 5th April a cheque of Rs.2000 is received from Mohan but is not deposited in the bank, hence it is taken in the cash column. On April 8, this cheque is endorsed in favour of Sohan, hence entry for payment is made in the cash column. Another alternative could be that you don't take this transaction in cash book and pass the following journal entry in the General Journal. But first choice of recording the transaction in the cash book is better.
Sohan A/c Dr. 2000
To Mohan A/c 2000