每分钟消耗电能W=Pt=120W*60S=7200J转3000转消耗电能W=3600000J转一转消耗W=1200J则1min转7200J/1200J=6转一昼夜(24h)耗电1.2KWh15min耗电W=pt=120W*15*60s=108000J启动次数=1.2*3600000/108000=40次(绝对正确!)
1KW.h3000r耗1度电,电210转耗0.07度电=0.07×3.6×10^6JP=W/t=0.07度/300/3600时=0.84千瓦=840瓦