Hey sorry just stuck on this one! Thanks!

Old fashioned bumper cars are powered by a charged ceiling and floor. A pole on the bumper car connects these two charged surfaces to give the car current to run. The difference in voltage between the plates is typically around 48 V. Estimate the height difference between the ceiling and floor. When radon in the ground decays it releases an alpha particle. Assuming the ceiling is negatively charged, the alpha particle could be accelerated towards the celling. It is not good for people to be hit with fast moving alpha particles. Mathematically show if this is something we need to be concerned about. Note: Think about the height of a person and how fast the particle could be moving when it hits them. Is it moving at a slow drift, or an appreciable speed of light like nuclear radiation?