A 125g sample of a radioisotope with a half life of 25 years is found in a basement after being misplaced for 75 years. What was the mass of the original sample?

Current enters a circuit at a: 1.positive terminal 2.negative terminal 3.low potential side 4.resistor

Ryan is examining the energy of the particles in a bar of gold. what is ryan most likely studying?

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.