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If the log had a mass of 30.5 kg, and the duck was swimming at 1.00 m/s, what is

ID: 1442826 • Letter: I

Question

If the log had a mass of 30.5 kg, and the duck was swimming at 1.00 m/s, what is the log's kinetic energy? Be sure to include units.

uck is swimming down a river and passes a slow moving log. If the duck is moving 2.50 times faster tnan the log, but the log has 3.25 times the kinetic energy of the duck, what is the ratio of the log's mass to the duck's mass? Number 20.31 If the log had a mass of 30.5 kg, and the duck was swimming at 1.00 m/s, what is the log's kinetic energy? Be sure to include units. Number Units 3.81

Explanation / Answer

Vd = velocoty of duck

Vl = velocity of log

Ml = mass of log

Md = mass of duck

according to question, Vd = 2.50*Vl ------------------------1

K.El = 3.25*K.Ed

( 1/2)*Ml*Vl2 = 3.25*(1/2)*Md*Vd2

Ml / Md = 3.25*( Vd/ Vl)2

Ml / Md = 3.25*( 2.50*Vl / Vl)2   ( from eq 1)

Ml/ Md = 20.31

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B) Ml = 30.5 kg

Vd = 1m/s

K.El = (1/2)*Ml*Vl2

= (1/2)*Ml*( Vd / 2.50)2   ( from eq 1)

= (1/2)*30.5*(1/ 2.50)2

= 2.44 J