Question

why did einstein write a letter to franklin d roosevelt

Answer 1

Heya

This refers to a famous letter that was actually written by Leo Szilard, on behalf of Albert Einstein. The letter was signed by Einstein and delivered to the then president of the United States, Franklin Roosevelt, on the 2nd of August 1939 in the early states of World War II.
The letter is historically important since in it, Einstein described how the Nazi Regime in Germany had started working on an Atomic Bomb which was more powerful than any weapon in History.This letter alerted the US and allied forced and eventually left to the start of the Manhattan project as a collaboration between US and the British Empire
By the end of the Manhattan project, the allied forced had the most advanced weapon on the planet.

HOPE UT HELPS☺️

Answer 2

Answer:

When the Nazis came to power in Germany, Einstein emigrated to the United States of America. Five years later, the discovery of nuclear fission in Berlin had American physicists in an uproar. Many of them had fled from Fascism, just as Einstein had, and now they were afraid the Nazis could build and use an atomic bomb. Einstein wrote a letter to Franklin Roosevelt to warn him of the consequences of the explosion of an atomic bomb.