An isotope of Iodine (atomic number 53) has a mass number of 123 and a half-life of 13 hours. It decays by emitting a beta particle. If the sample has an initial activity of 2000kBq what will be the activity 52 hours later.

An electron moves with a constant horizontal velocity of 3.0 × 106 m/s and no initial vertical velocity as it enters a deflector inside a tv tube. the electron strikes the screen after traveling 26 cm horizontally and 19 cm vertically upward with no horizontal acceleration. what is the constant vertical acceleration provided by the deflector? (the effects of gravity can be ignored.)

Aproton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?

Current vs. forcewhat type of relationship does this graph show?