Use these values: distance traveled is 30.0 km; time elapsed is 40.0 minutes; average power output is 370 watts. Determine the total energy expended by the cyclist, in kilojoules.

Explanation:

It is known that the relation between power and work is as follows.

           Power =

As it is given that power is 370 watts and time is 40 minutes. First, we will convert minutes into seconds as follows.

                 = 2400 sec

Now, total power or energy is calculated as follows.

              Power =

                         =        

                         = 888000 J

As 1 kJ = 1000 J. So, convert 888000 J into kJ as follows.

                  = 888 kJ

therefore, we can conclude that total energy expended by the cyclist is 888 kJ.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

increase masses, decrease separation