Physics
A block and tackle system of pulleys has velocity ratio 4.
(a) Draw a labelled diagram of the system indicating clearly, the direction of the load and effort.
(b) Calculate the potential energy of the load 100 kgf lifted by this pulley to a height 5 m. (g = 10 ms-2)
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Answer
(a)The labelled diagram of the system indicating clearly, the direction of the load and effort is shown below :
(b) Given,
m = 100 kg
h = 5 m
g = 10 ms-2
Then,
Potential Energy (U) = mgh = 100 × 10 × 5 = 5000 J
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