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计算题:若三相三线电能表处于满载,即电压互感器输出电压为U为100V,电流互感器输出电流I为5A,且有每周脉冲数n为1,电能表常数C为1500r/kWh,计算出每分钟输入终端的电量脉冲数。

答案

参考答案:

已知有功功率P=UIcos=1.732³100³5³cos

=866cos(W)

设cos=1,且P=0.866kW

每转时间

每分钟脉冲数=≈21.65(个)

在功率因数小于1的情况下,电能表输出脉冲数少于21.65个/min。

每分钟输入终端的电量脉冲约为21.65个。

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Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results (1) motivated behavior.
Motivation can be either positive or negative (2) direction. We may feel a driving force toward some object or condition, (3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away (4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives (5) needs, wants or desires, (6) negative drives as fears or aversions (7) , though negative and positive motivational forces seem to differ dramatically (8) terms of physical and sometimes emotional activity, they are basically similar in (9) they both serve to initiate and sustain human behavior. (10) this reason, researchers often refer (11) both kinds of drives or motives as needs, wants and desires.
Goals, (12) , can be either positive or negative. A positive goal is one toward (13) behavior is directed and it is often referred to as an approach object. A negative goal is (14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to (15) types simply as goals. Consider this example. A middle-aged woman may wish to remain (16) attractive as possible. Her positive goal is to appear desirable, and (17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin (18) aging, and therefore she may buy and use face creams. (19) the former case, she uses perfume to help her achieve her positive goal -- attractiveness; in the (20) case, she uses face creams to help avoid a negative goal -- wrinkled skin.