(1)150r÷2000r/KW·h=0.075KW·h=270000J 答:270000J .
(2)0.075KWh=270000J 答:270000J .
( 3)150r÷5min8*60min=1800r 1800r÷2000r/KW·h=0.9KW·h
P=W÷t=0.9KW·h÷1h=0.9kw=900w 答:900w.
(4)答:电功率小了,可能是电阻大了,因为P=U²÷R.
(1)150r÷2000r/KW·h=0.075KW·h=270000J 答:270000J .
(2)0.075KWh=270000J 答:270000J .
( 3)150r÷5min8*60min=1800r 1800r÷2000r/KW·h=0.9KW·h
P=W÷t=0.9KW·h÷1h=0.9kw=900w 答:900w.
(4)答:电功率小了,可能是电阻大了,因为P=U²÷R.