A child with mass of 25 kg gets into a toy car with mass of 80 kg on a playground, causing it to sink on its springs (with effective spring constant 791 N/m). An adult walks by and gives the top of the car a shove, causing it to undergo oscillations with amplitude 31 cm in the vertical direction. Assuming the oscillations are simple harmonic, what is the frequency of the oscillations?

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Power can be defined as a. the distance over which work was done. b. how much work can be done in a given time. c. all the work in an given area. d. the energy required to do work.

Arefrigerator uses r-134a as the working fluid and operates on the ideal vapor-compression refrigeration cycle except for the compression process. the refrigerant enters the evaporator at 120 kpa with a quality of 34 percent and leaves the compressor at 70°c. if the compressor consumes 450 w of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the cop of the refrigerator. (0.00644 kg/s, 800 kpa, 2.03)