7.4 PQ1 Apply the grid method to each situation. a. Calculate the energy in joules used by a 1 hp pump that is op- erating for 6 hours. Also, calculate the cost of electricity for this time period. Assume that electricity costs $0.15 per kW-hr. b. Amotor is being to used to turn the shaft of a centrifugal pump. Apply Eq. (7.2b) to calculate the power in watts corresponding to a torque of 100 Ibf-in and a rotation speed of 850 rpm. c. A turbine produces a power of 7500 ft-lbf/s. Calculate the power in hp and in watts.

7.4 PQ1 Apply the grid method to each situation. a. Calculate the energy in joules used by a 1 hp pump that is op- erating for 6 hours. Also, calculate the cost of electricity for this time period. Assume that electricity costs $0.15 per kW-hr. b. Amotor is being to used to turn the shaft of a centrifugal pump. Apply Eq. (7.2b) to calculate the power in watts corresponding to a torque of 100 Ibf-in and a rotation speed of 850 rpm. c. A turbine produces a power of 7500 ft-lbf/s. Calculate the power in hp and in watts.