Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_16768245_2 (longitude VARCHAR, diameter VARCHAR)

### Question ###
How many longitudes have a diameter of 224.0?

### Accurate SQL ###

SELECT COUNT(longitude) FROM table_16768245_2 WHERE diameter = "224.0"