**Summary of Transactions:**

1. Started business with:
- Cash Rs. 50,000
- Goods Rs. 20,000

2. Goods purchased for cash:
- Amount: Rs. 15,000

3. Salary paid:
- Amount: Rs. 2,000

4. Salaries outstanding:
- Amount: Rs. 500

5. Prepaid insurance premium:
- Amount: Rs. 1,000

6. Rent paid in advance:
- Amount: Rs. 500

7. Wages due but not paid:
- Amount: Rs. 100

8. Loan taken from bank:
- Amount: Rs. 20,000

9. Machinery purchased:
- Amount: Rs. 5,000

**Explanation of Transactions:**

1. **Started business with cash and goods:**
- The business started with an initial investment of:
- Cash: Rs. 50,000
- Goods: Rs. 20,000
- This means the owner contributed Rs. 50,000 in cash and Rs. 20,000 worth of goods to the business.

2. **Goods purchased for cash:**
- The business purchased goods for cash worth Rs. 15,000.
- This transaction involves an increase in the inventory (goods) and a decrease in cash.

3. **Salary paid:**
- The business paid Rs. 2,000 as salary to its employees.
- This transaction involves a decrease in cash (salary expense) and an increase in the liability of salary payable.

4. **Salaries outstanding:**
- The business has an outstanding amount of Rs. 500 in unpaid salaries.
- This transaction involves an increase in the liability of salaries payable.

5. **Prepaid insurance premium:**
- The business paid Rs. 1,000 in advance for insurance coverage.
- This transaction involves a decrease in cash (prepaid expense) and an increase in the asset of prepaid insurance.

6. **Rent paid in advance:**
- The business paid Rs. 500 in advance for rent.
- This transaction involves a decrease in cash (prepaid expense) and an increase in the asset of prepaid rent.

7. **Wages due but not paid:**
- The business has an amount of Rs. 100 due for wages, but it has not been paid yet.
- This transaction involves an increase in the liability of wages payable.

8. **Loan taken from bank:**
- The business took a loan of Rs. 20,000 from a bank.
- This transaction involves an increase in cash (loan received) and an increase in liability (loan payable).

9. **Machinery purchased:**
- The business purchased machinery worth Rs. 5,000.
- This transaction involves a decrease in cash and an increase in the asset of machinery.

By analyzing these transactions, we can see how they impact the various elements of the accounting equation, such as assets, liabilities, and owner's equity. These transactions are crucial for recording and tracking the financial activities of the business.