Question

Who discovered radioactivity?

Hint:

Think of the French physicist who studied uranium salts and photographic plates in 1896.

Answer 1

The correct answer is Henri Becquerel.
Becquerel was a French physicist. In 1896 he was working with uranium salts and photographic plates.
He found that the uranium salts fogged a photographic plate even without any exposure to sunlight. This showed the salts gave off rays on their own.
He had found a new kind of energy coming from inside the atom. Later this property was named radioactivity.
Marie Curie and Pierre Curie built on his work. They found more radioactive elements such as polonium and radium.
Becquerel shared the 1903 Nobel Prize in Physics with the Curies for this discovery.