Cathode rays causes an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays

Answer Details

When cathode rays pass through a perforated anode, they cast a shadow of the object placed behind the anode on the screen. This happens because cathode rays are negatively charged particles and travel in straight lines. Therefore, they are blocked by the solid object (perforated anode) and form a shadow on the screen where they do not pass through. This observation rules out the possibility that cathode rays are positively charged or have mass, and indicates that they are negatively charged particles that travel in straight lines.