Mark 2 right about radiation from from the beta source in the picture Positive charge
Negative charge
No charge
Helium cores
Hydrogen cores
Electrons
Electromagnetic radiation

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.