Question

Ile czasu trfała podróż samochodem o mocy 48 kw jeżeli wykonał on prace 34MJ

Answer 1

P = 48kW = 48 000W
W = 34MJ = 34 000 000J

P = W/t => t = W/P

t = 34 000 000J/48 000W = 708,3s ~ 12minut

Answer 2

Dane: 
P = 48 kW = 48 000 W 
W = 34 MJ = 34 000 000 J 
szukane: 
t = ? 

P = W/t   I*t 
P * t = W   /:P 
t = W/P 
t = 34000000J/48000W = 708,(3) s 
t = 708,3 s = 11,805 min = 11min 48s