Hello
I have a question about oscillation of a pendulum.
"I want to make vacuum in the place and hang a pendulum there in order to constant oscillation , because I've heard that the only force making damped oscillation is the force of air molecules."
Is the above sentence scientifically correct ?
Can I make a constant oscillation ?
Please answer my question/
Thanks a lot.

Strictly, yes, but a perfect vacuum is impossible to create. Also many other things affect the period of a pendulum, if you want the period to always be constant.

As Cap said, there are several factors that may affect an oscillating pendulum, namely the way you tied your bob, the way your thread is attached to your support.

hello
I have a question about oscillation of a pendulum.
"I want to make vacuum in the place and hang a pendulum there in order to constant oscillation , because I've heard that the only force making damped oscillation is the force of air molecules."
Is the above sentence scientifically correct ?
Can I make a constant oscillation ?
please answer my question/
Thanks a lot.

To a first approximation, the only force damping a pendulum is air. Also, even a reasonable vacuum eliminates almost all of that.

There are usually practical forces affecting pendulums. Most pendulums have some sort of pivot point -- an axle. Friction in the axle is a larger problem than air friction.

There are other ways to make constant oscillations. The most common nowadays is to create an electrical circuit with a quartz crystal that controls the frequency of oscillation and use that to perform whatever function you want the oscillator to perform.