Answer:
We can define a fixed asset as tangible asset that one can touch. Like a house or jewelry. These cannot be easily converted into cash and they produce profit in the long run.
But most liquid assets are intangible. Like - short term securities, short term bonds, checking and savings accounts etc. Liquid assets also include current assets like cash, bank balance etc.
In other words, liquid assets can be readily converted into cash and sold on a short notice.