Which of the following radioactive emissions is the most penetrating?

alpha particles
beta particles
gamma rays

Apassenger walks toward the rear of a moving train. describe her motion as seen from a reference point on the train. then describe it from a reference point on the ground

Ametal ball with a mass of 0.028 kg is dropped from rest at a height of 1.0 meters above the ground. assuming the energy in the ball is conserved, how much kinetic energy will the ball have when it is 0.5 meters above the ground?

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2