The record number of boat lifts, including the boat and its ten crew members was achieved by sami heinonen and juha-matti räsänen of finland in 2000. they lifted a total mass of 653.2 kg approximately 4 in. off the ground a total of 24 times. estimate the total mechanical work done by the two men in lifting the boat 24 times, assuming they applied the same force to the boat during each lift. (neglect any work they may have done allowing the boat to drop back to the ground.)

15625.03 Joule

Explanation:

The force which the two people have to exert on the mass in order to lift it is

F=mg

Where,

m = Mass = 653.2 kg

g = Acceleration due to gravity = 9.81 m/s²

At one time the people lifted the mass 4 in

Energy required in one time

Energy required in 24 times

Energy required to raise the mass 4 inches 24 times is 15625.03 Joule

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.