The rate of doing work, P=Fv or P=Tω.
Power P=dW/dt=F·v; for rotation P=Tω. Units are watts (1 W = 1 J/s). Efficiency η=P_out/P_in. Engine power is torque times angular speed.
A motor producing 50 N·m at 3000 rpm delivers about 15.7 kW.
Power ties energy to time, and it is what matters when choosing motors, engines and pumps for a required performance.
The rate of doing work, P=Fv or P=Tω.
Power ties energy to time, and it is what matters when choosing motors, engines and pumps for a required performance.
Multiply torque in newton-metres by angular speed in radians per second to get watts.
Higher power usually means more size, weight and cost, so the best choice matches the duty cycle and the efficiency at the operating point.
Typical applications include sizing a motor for a lift that must rise at a set speed, calculating the power of an engine from torque and speed and estimating the power needed to drive a fan at a given airflow.
Study "Conservation of energy" first (topic 29 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
1 hp ≈ 746 W. Instantaneous vs average power. Power limits acceleration and climbing.
A motor producing 50 N·m at 3000 rpm delivers about 15.7 kW.
The next topic is "Impulse and momentum", which builds directly on this one.
It is classed as Beginner in Engineering Mechanics (topic 30 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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