pagina  52

 

                                                          Rendement

 
       
 


 


                                         Het rendement is het percentage nuttige energie die geproduceerd wordt.


                                         Voorbeeld 1:

                                                                                 

                                                                elektriciteit                             licht         en         warmte

                                                                 50.000 J                                                   5 000 J               45 000 J

                                                       Bereken het rendement.

                                                        50 000 Joule is 100 %

                                                        1 % is 500J

                                                        Hoe vaak past 1% in 5000 J ?

                                                        5000 / 500 = 10%


                                                       De nuttige (goede) energie is licht. 5000 J is 10 %

                                                       Het rendement is 10% .     




                                          Voorbeeld 2:

                                                                                         

                                                              beweging                        elektriciteit         en         warmte

                                                    Een fietsdynamo gebruikt ongeveer 50 W aan beweging.
                                                    De dynamo draait 2 minuten. Er ontstaat 1500 J electriciteit.
                                                    Bereken het rendement.

                                                    50 W is 50 J/s.      2 min. = 120 sec.

                                                   formule:  energie =  vermogen  X  tijd

                                                                     E       =      P         X   t
                                                                     E       =    50 J/s   X   120 s
                                                                     E       =    6000 J


                                                              beweging                        elektriciteit         en         warmte
                                                                6000 J                                               1500 J

                                                    Hoeveel % is 1500 J ?

                                                     1 % = 60 J

                                                     1500 / 60  =  25 %

                                                     De dynamo heeft een rendement van 25 %