A man uses a rod of length 5.0m to lift a 700 kg marble. The fulcrum is 0.50m from the end of the bar that is under the marble. Calculate the mechanical advantage and minimum effort required to lift the load. If the efficiency of this system is 90% determine it's velocity ratio.

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.

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.

in order to follow the instructions and complete the statements, i need to use data from table c of your student guide. can you think of a way to let me see your student guide for a while ? i can't answer the question without the data in table c.