A500. gram sample of nickle-63 has a half-life of 100. years and has decayed for 500. years. how much of the original 500. gram sample remains?

87.1 grams
574 grams
16,000 grams
15.6 grams

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

Acalorimeter uses the principle that thermal energy flows from hotter material to colder material until both reach the same

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.