Water flows (v approx. 0) over a dam at the rate of 660 kg/s and falls vertically 86 m before striking the turbine blades. Calculate the rate at which mechanical energy is transferred to the turbine blades, assuming 53% efficiency.

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To calculate the rate at which mechanical energy is transferred to the turbine blades, we need to use the following formula:

Power = Efficiency * Mass Flow Rate * Gravitational Acceleration * Height

First, let's determine the variables we need:

Efficiency = 53% = 0.53 (expressed as a decimal)
Mass Flow Rate = 660 kg/s
Gravitational Acceleration = 9.8 m/s²
Height = 86 m

Now, let's substitute these values into the formula and calculate the rate at which mechanical energy is transferred to the turbine blades:

Power = 0.53 * 660 kg/s * 9.8 m/s² * 86 m

First, let's calculate the value inside the parentheses:

660 kg/s * 9.8 m/s² * 86 m = 542,136 kg·m²/s³

Substituting this value into the formula:

Power = 0.53 * 542,136 kg·m²/s³

Now, let's calculate the power:

Power = 287,005 kg·m²/s³

Therefore, the rate at which mechanical energy is transferred to the turbine blades is approximately 287,005 kg·m²/s³.