Correctly to calculate action of force rotating a body, define a point of its application and distance from this point to a rotation axis. It is important for definition of technical characteristics of various mechanisms. Torque of the engine can be calculated if its power and frequency of rotation is known.
It is required to you
- Ruler, dynamometer, tachometer, tester, teslametr.
Instruction
1. Define a point or an axis around which the body rotates. Find a point of application of force. Connect a point of application of force and a point of rotation, or lower a perpendicular on a rotation axis. Measure this distance, it is called "force shoulder". You take measurement in meters. Measure force in newtons by means of a dynamometer. Measure a corner between a shoulder and a vector of force. For calculation of the rotating moment find the work of force on a shoulder and a sine of the angle of M=F between them • r· sin(α). Receive result in newtons on meter.
2. If it is necessary to measure the rotating moment of any engine learn its rated power which is specified in technical documentation. If it is not specified, measure it in any way. Express engine capacity in kilowatts.
3. Measure by the tachometer the frequency of rotation of a shaft in revolutions per minute. For obtaining value of the rotating moment, increase the received engine capacity by coefficient 9550 and divide into the measured frequency.
4. If to place a frame with current in magnetic field, it begins rotation. It will be the simplest model of the electric motor. To find its rotating moment, measure by means of a tester current in the conductor which makes a frame. From an axis of its rotation by means of a ruler measure distance to the vertical parties of a frame. Force will also act on them.
5. Measure length of vertical conductors. By means of a teslametr measure induction of magnetic field in which the frame rotates. At rotation force has to be always perpendicular to a shoulder. In this case the rotating frame moment with current will be equal to performing induction on current, lengths of the vertical conductor and a shoulder. As in a frame double two vertical conductors, result: M=2·B·I· d·r where B is induction, I - the current, d - length of the conductor, r - a shoulder. Eesli is a lot of rounds, increase the moment of one round by their quantity.