How did Hershey and Chase prove that DNA is the hereditary material?

Explanation

Hershey and chase worked with virus that inflects bacteria called bacteriophage.
They grew some viruses on radio active phosphorous medium and some on radio sulphur. Virus grown in the presence of radio active phosphorous contained radioactive DNA & those grown in radioactive sulphur contained radio active protein.

Radio active phages were allowed to attach to the E.coli bacteria. As the infection proceeded, the viral coats were removed from the bacteria by agitating them in a blender, The viral particles were separated from bacteria by spinning them in a centrifuge.
Bacteria which was infected with virus that had radio active phosphorous were radio active, indicating that DNA was the material that has passed from virus to bacteria. Bacteria that was infected with radioactive sulphur were not radio active. There fore DNA is the genetic material that has passed from virus to bacteria.