Britain started work on an atomic bomb before the Manhattan Project got underway. All research was transferred to the US, due to that country's industrial capacity (and remoteness from Axis bombers) so essentially Britain "had the bomb" at the same time the US did. The first purely British bomb wasn't exploded until 1952, however.
This answer comes from Wikipedia under the heading of Manhattan Project.
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Because of the complexity of an implosion-style weapon, it was decided that, despite the waste of fissile material, an initial test would be required. The first nuclear test took place on July 16, 1945, near Alamogordo, New Mexico, under the supervision of Groves's deputy Brig. Gen. Thomas Farrell. Oppenheimer gave the test the code name "Trinity".
The Fat Man bomb was dropped in August after the successful test in July.
Preliminary studies started in the US in 1942. The Manhattan Project started in 1943 and started making its first bombs in June 1945.
The USSR started their project about the same time the US did, but because of the war was not able to get resources to build the industrial infrastructure needed until after the end of WW2. They began building their first bombs in 1949.
Basically, once the decision is made to build atomic bombs it takes a typical industrialized country 3 to 4 years to build the industrial infrastructure needed to process and make the materials and parts before they can actually start making atomic bombs.
Further to previous answer,yes Germany & Jaapan were working onit, but it was actually BRITAIN who passed on the research done in 1940 to USA . Called "The Manhattan Project" Britain handed over to the USA in 1941 when they came on side in WW2.The work was carried out by US physicist Oppenheimer at Los Alamos, New Mexico.After 1 test explosion, the USA dropped their 2 bombs on Japan on 6th & 9th August 1945.
The Manhattan Project to create the bomb started in 1942. The first test of the bomb was on July 16, 1945. The bomb was dropped on Japan August 8, 1945.
1932
1942
the us created the atomic bomb
To defend against a possible Nazi atomic bomb!
well, the atomic bomb research was done by Robert oppenheimer. the original creation or idea was from albert Einstein
The first atomic bomb was dropped on Hiroshima, Japan ; another on Nagasaki, Japan, 3 days later.
The US .
Both atomic bombs dropped on Japan were successful. What gave you the idea they weren't?
the us created the atomic bomb
We developed the first working atomic bomb but, GER. made up the idea.
If you consider the US atomic bomb is a Christian bomb, the French atomic bomb is also Christian bomb and so on, then you can name the Pakistani atomic bomb an Islamic bomb.
The US dropped the atomic bomb onto Japan on August 1945.
To defend against a possible Nazi atomic bomb!
Because even in the U.S. and Japan everyone hated the idea because an atomic bomb could kill everyone including children.
Franklin D Roosevelt did. He approved the atomic bomb idea.
The hydrogen bomb.
1945
What gave you that idea? It isn't obsolete in any way. In fact every Hydrogen bomb contains an Atomic bomb as its primary stage.
well, the atomic bomb research was done by Robert oppenheimer. the original creation or idea was from albert Einstein