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A tuning fork has a frequency of 400 Hz and hence a period of 2.50 x 10-3 s.If the tuning fork is in an inertial frame of reference moving by the observer at speed of 0.750 c,what is the frequency of the fork as measured by the observer? (Assume that measurements are strictly by optical means and that the speed of sound waves in air is not pertinent here) .
African Americans
A racial or ethnic group in the United States with ancestry from the black racial groups of Africa, whose history and culture have significantly shaped American society and politics.
1945-1954
This period marks the aftermath of World War II and the onset of the Cold War, witnessing significant political, social, and economic changes globally.
Economic Boom
A period of significant economic growth and prosperity within a country or region, characterized by increases in employment, production, and consumer spending.
Second World War
A global conflict from 1939 to 1945, involving most of the world's nations, characterized by significant battles, genocide, and the ultimate use of nuclear weapons.
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