Question

The first thermionic valve was invented by
A) Thomas Edison
B) Richardson
C) J.A. Fleming
D) Lee De Forest

Answer 1

C) J.A. Fleming or John Ambrose Fleming

Answer 2

The first thermionic valve was invented by
A) Thomas Edison
B) Richardson
C) J.A. Fleming
D) Lee De Forest

${ \underline{\textbf{J.A. Fleming}}}$