Power calculation method is as follows:
1, direct calculation method: for some simple mechanical or electrical systems, can be directly based on the power of the definition of the formula P = W / t to calculate. For example, for a resistor with a resistance of R, the current through it is I, the power consumed in time t is W=I?Rt, so that the power P=W/t=I?R can be calculated.
2, analogical method: by analogy with other systems to calculate power. For example, an object moving in the water when the resistance is proportional to the square of the velocity, that is, F = kv?, where k is the resistance coefficient. It can be learned experimentally that the power produced by the resistance of the object moving with velocity v in the water is P=Fv=kv?.
3, formula method: use the formula for power P = Fv to calculate. Where F is the force and v is the velocity. When the force and velocity are perpendicular to each other, the formula can be simplified to P=Fvcosθ, where θ is the angle between the force and velocity.
4, torque method: by measuring the torque and speed to calculate the power. According to the defining equation of torque T=F×R, we can get F=T/R. Then combining the rotational speed n and angular speed ω (ω=2πn), we can get the power P=Tω/R.
Power application scope:
1, energy conversion and utilization: power is one of the core concepts of energy conversion and utilization. In the fields of electric power, heat, chemical industry, aerospace and so on, power conversion and utilization plays a vital role. By improving the efficiency of energy utilization, it can reduce energy consumption and environmental pollution, and promote sustainable development.
2, mechanical equipment and electrical appliances: power is the basis for the normal operation of mechanical equipment and electrical appliances. In all kinds of mechanical equipment and electrical appliances, power plays a driving and controlling role, to ensure that the normal operation of the equipment and achieve the required working effect.
3, communications and information technology: the development of communications and information technology can not be separated from the power of support. For example, in wireless communications, the size of the power directly affects the signal coverage and quality; in the computer field, power is an important factor in the stable operation of data centers, servers and other equipment.
4, transportation: transportation requires a lot of power to drive vehicles, ships, aircraft and other vehicles. With the popularization of new energy vehicles, the position of power drive system in transportation is becoming more and more important.
5, medical equipment: medical equipment in many high-end equipment needs high-power power support, such as CT, MRI, etc.. At the same time, with the development of medical technology, more and more portable medical equipment on the power demand is also increasing.