CoE questions

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a) W = m x g
= 50 x 100
= 500N
b) GPE = mgh
= 50 x 10 x 4
= 2000J
c) Total energy at start = Total energy at end
KE = 2000J

Q3
a) GPE = mgh
= 35 x 10 x 30
= 10500J
b) Total energy at start = Total energy at end
KE = 1/2 x m x v x v
10500= 1/2 x 35 x v x v
v= 24.5 m/s
c) Friction and air resistance
Some of GPE turned into heat; not all trasnferred to KE

PFY p.121

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Collins, p.91

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