Power questions

PFY, p. 120

f) Power is the rate of doing work

Power ( in Watts) = Work done ( in Joules) / time ( in seconds)

g) 1 watt is a rate of working of one joule per second

13) P = E / t = 1000/5= 200 W

14)   Wd = F X D = 300 X 2 = 600 J

P = E/t = 600/6 = 100 W

16)   A) Wd = F X D = 3000 X 10 = 30000J

P= E/t = 30000/4 = 7500 W  

b) 7.5 Kilowatts