You have to use both hands to create a sound of clap. It is the same as you need a musician and musical instrument to create a music. The musician should use the instrument to create the music. Without the musician there is no music and without musical instruments there is no music either. Both are needed to create music. This is basic to understand about music. But you should move above.
The musical instrument is just a peripheral for the musician to create music. What happens when he moves to a higher platform he can create music without the musical instrument. He can hear music by just practicing without the aid of an instrument.
Is it possible?
Yes, If you watch the musician he applies certain rules while operating an instrument. The string of the instrument that produces the music. Actually string is a mediator between musician and the music. If he meditates he can remove the instrument out of the way and directly reach the music. The peripheral will disappear in a higher form of life and you are directly connected to the nectar. The direct connection to the nectar is called one hand clapping.
Your one hand is enough for clapping and another hand is just a peripheral is no more required and you can directly reach the sound without the help of another hand. It is like hitting the bird without an arrow. An arrow was considered peripheral and useful for beginners and once you become a master you don’t need an arrow to pull down the bird, just the eyes are enough!
To understand better
Have you seen a mother understanding her child without the aid of language.. that’s it.