Apositively-charged object with a mass of 0.129 kg oscillates at the end of a spring, generating elf (extremely low frequency) radio waves that have a wavelength of 3.86 × 10^7 m. the frequency of these radio waves is the same as the frequency at which the object oscillates. what is the spring constant of the spring?

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.