Answer;
Thomson's experiments are important because they showed that the atom is clearly composed of smaller particles.
Step-by-step explanation;
J.J. Thomson used magnetic and electric fields to measure the mass-to-charge ratio of a cathode ray particle. Thomson set out to prove that the cathode rays produced from the cathode were actually a stream of negatively charged particles called electrons.
J.J. Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. He proposed the plum pudding model of the atom, which had negatively-charged electrons embedded within a positively-charged "soup."