किसी दिए गए परावैद्युत (dielectric) पदार्थ के लिए, तापमान में वृद्धि के साथ आयनिक ध्रुवणता (ionic polarizability) किस प्रकार परिवर्तित होती है?

The maximum electric field strength above which an insulating material begins to break down and conduct is called _____________ strength.

In practice, the choice of a liquid dielectric for a given high-voltage application is made primarily on the basis of its: